Eutrophicated

J Environ Manage, 2005 Feb, 74(3), 195 - 205
Life cycle assessment of EPS and CPB inserts: design considerations and end of life scenarios; Tan RB et al.; Expanded polystyrene (EPS) and corrugated paperboard (CPB) are used in many industrial applications, such as containers, shock absorbers or simply as inserts . Both materials pose two different types of environmental problems . The first is the pollution and resource consumption that occur during the production of these materials; the second is the growing landfills that arise out of the excessive disposal of these packaging materials . Life cycle assessment or LCA will be introduced in this paper as a useful tool to compare the environmental performance of both EPS and CPB throughout their life cycle stages . This paper is divided into two main parts . The first part investigates the environmental impacts of the production of EPS and CPB from 'cradle-to-gate', comparing two inserts-both the original and proposed new designs . In the second part, LCA is applied to investigate various end-of-life cases for the same materials . The study will evaluate the environmental impacts of the present waste management practices in Singapore . Several 'what-if' cases are also discussed, including various percentages of landfilling and incineration . The SimaPro LCA Version 5.0 software's Eco-indicator 99 method is used to investigate the following five environmental impact categories: climate change, acidification/eutrophication, ecotoxicity, fossil fuels and respiratory inorganics.

Huan Jing Ke Xue, 2004 Sep, 25(5), 138 - 42
{Cycling characteristics of phosphorus in an urban lake and its eutrophication potentiality}; Zhou QX et al.; Input and output pathway, fluxes, characteristics and temperature-increasing responses of phosphorus cycling in the East Lake located at the centre of Linhai City, Zhejiang Province, China were analyzed . On the basis of the annual field observation on the lake, it was indicated that chlorophyll a in water was being increased at the average rate of 0.14-0.56 microg/L, the transparence in water was being decreased at the average rate of 0.38-0.49 m, and dissolved oxygen in water was being reduced at the average rate of 0.21-0.71 mg/L . Relationships between the representative measurable parameters which can reflect the eutrophication potentiality of a lake and total phosphorus (TP) in water were set up, thus revealing that a change of phosphorus in lake water can be used to comprehensively judge the nutrition situation of a lake through forecasting changes in other factors and their relationships . This work can thus provide a scientific basis for decreasing eutrophication and improving water quality of lakes.

Ying Yong Sheng Tai Xue Bao, 2004 Aug, 15(8), 1447 - 50
{Purification of eutrophicated water by aquatic plant}; Tong C et al.; In this study, aquatic plants were used to control the pollution of eutrophicated water . The results showed that aquatic plants had a higher ability to remove total nitrogen (TN), total phosphorus (TP) and nitrate nitrogen . Among them, foxtail alga (Myriophyllum verticillatum) and grain leaf pondweed (Potamogeton maackianus) could effectively remove TN (83.84% and 77.54%), TP (91.3%) and nitrate nitrogen (95.85% and 90.65%), but had no significant effect on removing ammonia nitrogen (only 14% to 70%) . Sediment shielded by plastic could prolong the release of the nutrients from it for 15 to 20 days, and show the compensation effect later . The results also showed that aquatic plants could greatly improve the transparency of water, but could not improve the COD and DO of water effectively.

Proc R Soc Lond B Biol Sci, 2004 Nov 22, 271(1555), 2361 - 5
Water turbidity by algal blooms causes mating system breakdown in a shallow-water fish, the sand goby Pomatoschistus minutus; Jarvenpaa M et al.; Eutrophication as a result of human activity has resulted in increased algal blooms and turbidity in aquatic environments . We investigated experimentally the effect of algal turbidity on the mating system and sexual selection in the sand goby, Pomatoschistus minutus (Pallas), a marine fish with a resource-defence mating system and paternal care . Owing to male-male competition and female choice, large males can monopolize multiple mates, while some males do not achieve mating at all . We show that the number of eggs laid was the same in both turbid and clear tanks but that mating success was more evenly distributed among males in turbid than in clear water . The opportunity for sexual selection was lower in turbid conditions . In turbid conditions mating success was less skewed towards large males . Our results suggest that increased turbidity can change mating systems and decrease the opportunity for sexual selection as well as selection intensity.

Water Res, 2004 Dec, 38(20), 4446 - 54
A practical application of Droop nutrient kinetics (WR 1883); Cerco CF et al.; Algal growth kinetics based on internal phosphorus concentration were incorporated into an existing eutrophication model . Application to a closed system resulted in damped oscillations in algal biomass and phosphate relative to a model with fixed composition . Peak biomass did not differ substantially, however, from that attained using a model with fixed, minimal phosphorus-to-carbon ratio . Sensitivity analyses were conducted following model application to the lower St . Johns River, Florida . Factor-of-two changes in key parameters had little influence on computed chlorophyll . Varying model parameters exerted a larger influence on dissolved phosphate concentration . We conclude Droop kinetics present a mechanism for regulating computed nutrient concentrations rather than computed chlorophyll concentrations.

J Environ Qual, 2004 Nov-Dec, 33(6), 2201 - 9
Rainfall timing and poultry litter application rate effects on phosphorus loss in surface runoff; Schroeder PD et al.; Phosphorus (P) in runoff from pastures amended with poultry litter may be a significant contributor to eutrophication of lakes and streams in Georgia and other areas in the southeastern United States . The objectives of this research were to determine the effects of litter application rate and initial runoff timing on the long-term loss of P in runoff from surface-applied poultry litter and to develop equations that predict P loss in runoff under these conditions . Litter application rates of 2, 7, and 13 Mg ha(-1), and three rainfall scenarios applied to 1- x 2-m plots in a 3 x 3 randomized complete block design with three replications . The rainfall scenarios included (i) sufficient rainfall to produce runoff immediately after litter application; (ii) no rainfall for 30 d after litter application; and (iii) small rainfall events every 7 d (5 min at 75 mm h(-1)) for 30 d . Phosphorus loss was greatest from the high litter rate and immediate runoff treatments . Nonlinear regression equations based on the small plot study produced fairly accurate (r(2) = 0.52-0.62) prediction of P concentrations in runoff water from larger (0.75 ha) fields over a 2-yr period . Predicted P concentrations were closest to observed values for events that occurred shortly after litter application, and the relative error in predictions increased with time after litter application . In addition, previously developed equations relating soil test P levels to runoff P concentrations were ineffective in the presence of surface-applied litter.

J Environ Qual, 2004 Nov-Dec, 33(6), 2174 - 82
Effects of near-surface hydraulic gradients on nitrate and phosphorus losses in surface runoff; Zheng FL et al.; Phosphorous (P) and nitrogen (N) in runoff from agricultural fields are key components of nonpoint-source pollution and can accelerate eutrophication of surface waters . A laboratory study was designed to evaluate effects of near-surface hydraulic gradients on P and N losses in surface runoff from soil pans at 5% slope under simulated rainfall . Experimental treatments included three rates of fertilizer input (control {no fertilizer input}, low {40 kg P ha(-1), 100 kg N ha(-1)}, and high {80 kg P ha(-1), 200 kg N ha(-1)}) and four near-surface hydraulic gradients (free drainage {FD}, saturation {Sa}, artesian seepage without rain {Sp}, and artesian seepage with rain {Sp + R}) . Simulated rainfall of 50 mm h(-1) was applied for 90 min . The results showed that near-surface hydraulic gradients have dramatic effects on NO(3)-N and PO(4)-P losses and runoff water quality . Under the low fertilizer treatment, the average concentrations in surface runoff from FD, Sa, Sp, and Sp + R were 0.08, 2.20, 529.5, and 71.8 mg L(-1) for NO(3)-N and 0.11, 0.54, 0.91, and 0.72 mg L(-1) for PO(4)-P, respectively . Similar trends were observed for the concentrations of NO(3)-N and PO(4)-P under the high fertilizer treatment . The total NO(3)-N loss under the FD treatment was only 0.01% of the applied nitrogen, while under the Sp and Sp + R treatments, the total NO(3)-N loss was 11 to 16% of the applied nitrogen . These results show that artesian seepage could make a significant contribution to water quality problems.

Appl Environ Microbiol, 2004 Nov, 70(11), 6559 - 68
Phylogenetic characterization of methanogenic assemblages in eutrophic and oligotrophic areas of the Florida Everglades; Castro H et al.; Agricultural activities have produced well-documented changes in the Florida Everglades, including establishment of a gradient in phosphorus concentrations in Water Conservation Area 2A (WCA-2A) of the northern Everglades . An effect of increased phosphorus concentrations is increased methanogenesis in the eutrophic regions compared to the oligotrophic regions of WCA-2A . The goal of this study was to identify relationships between eutrophication and composition and activity of methanogenic assemblages in WCA-2A soils . Distributions of two genes associated with methanogens were characterized in soils taken from WCA-2A: the archaeal 16S rRNA gene and the methyl coenzyme M reductase gene . The richness of methanogen phylotypes was greater in eutrophic than in oligotrophic sites, and sequences related to previously cultivated and uncultivated methanogens were found . A preferential selection for the order Methanomicrobiales was observed in mcrA clone libraries, suggesting primer bias for this group . A greater diversity within the Methanomicrobiales was observed in mcrA clone libraries than in 16S rRNA gene libraries . 16S rRNA phylogenetic analyses revealed a dominance of clones related to Methanosaeta spp., an acetoclastic methanogen dominant in environments with low acetate concentrations . A significant number of clones were related to Methanomicrobiales, an order characterized by species utilizing hydrogen and formate as methanogenic substrates . No representatives of the orders Methanobacteriales and Methanococcales were found in any 16S rRNA clone library, although some Methanobacteriales were found in mcrA libraries . Hydrogenotrophs are the dominant methanogens in WCA-2A, and acetoclastic methanogen genotypes that proliferate in low acetate concentrations outnumber those that typically dominate in higher acetate concentrations.

Adv Parasitol, 2004, 57, 191 - 253
Review of the trematode genus Ribeiroia (Psilostomidae): ecology, life history and pathogenesis with special emphasis on the amphibian malformation problem; Johnson PT et al.; Trematodes in the genus Ribeiroia have an indirect life cycle involving planorbid snails as first intermediate hosts, fishes or amphibians as second intermediate hosts and birds or mammals as definitive hosts . Although rarely pathogenic in definitive hosts, Ribeiroia infection can cause severe pathology and mortality in snails and amphibians . This group of parasites has gained notoriety for its prominent rol in the recent rash of amphibian deformities in North America . Under some circumstances, these malformations may enhance parasite transmission by rendering infected amphibian hosts more susceptible to definitive host predators . However, increasing reports of malformations in North American amphibian populations emphasize the importance of understanding infection patterns . Here we review important aspects of the biology, ecology, life cycle and pathogenesis of parasites in the genus Ribeiroia and identify priorities for future research . Based on available morphological descriptions and preliminary molecular data, three species of Ribeiroia are recognized: R . ondatrae in the Americas, R . marini in the Caribbean and R . congolensis/C . lileta in Africa . We further evaluate the influence of abiotic and biotic factors in determining the intensity and prevalence of Ribeiroia infection and malformations in amphibians, highlighting the importance of habitat alteration and secondary factors (e.g . aquatic eutrophication, contaminants) in promoting infection . Although not a "new" parasite, Ribeiroia may have increased in range, prevalence, or intensity in recent years, particularly within amphibian hosts . Nevertheless, while much is known about this intriguing group of parasites, there remains much that we do not know . Particular importance for future research is placed on the following areas: evaluating the phylogenetic position of the genus, establishing the molecular mechanism of parasite-induced malformations in amphibians, isolating the drivers of parasite transmission under field conditions and studying the consequences of malformations for parasite and host populations . Investigation of these questions will benefit enormously from a multidisciplinary approach that effectively integrates parasitology, developmental biology, immunology, herpetology and aquatic ecology.

Environ Geochem Health, 2004 Jun-Sep, 26(2-3), 97 - 103
Soil quality evolution after land use change from paddy soil to vegetable land; Cao ZH et al.; A survey was done in 15 typical villages, 150 soil and 86 vegetable plant samples were taken in Jiaxin prefecture of the Taihu Lake region, northern Zhejian province . Results indicate that after 15-20 years land use changed from the paddy rice-wheat (or oilseed rape) double cropping system, to a continuous vegetable land has caused soil quality dramatic change . (1) Acidification: average soil pH was 5.4; about 61% of total samples were pH < 5.5 . It was 0.9 units lower than 10 years ago with same upland vegetable cultivation and was 1.2 units lower than soil pH of paddy rice-wheat (or oilseed rape) rotation . (2) Fertilizer salt accumulation: the average salt content was 0.28%, among these about 36.2% of the total samples contained more than 0.3% . (3) Nitrate N and available phosphorus (P) over accumulation: on average it was 279 mg NO3-N/kg, and 45-115 mg P/kg . Nitrate N four times higher and available P 4-10 times more than it is in present paddy rice-wheat rotation soils respectively . This has caused wide concern because of possible groundwater and well drinking water pollution by leached nitrate N and the P losses to water by runoff from vegetable lands induce surface water eutrophication.

Ambio, 2004 Aug, 33(6), 316 - 23
Environmental impact assessment of salmonid feeds using Life Cycle Assessment (LCA); Papatryphon E et al.; Understanding the environmental burdens associated with aquafeeds is a critical component for assessing and improving the environmental performance of aquaculture . The aim of the study was to assess the environmental impacts associated with feeds for rainbow trout production in France, using Life Cycle Assessment (LCA) . The stages assessed are: the extraction of the raw materials, the production and transformation of the primary ingredients used, the manufacturing of the feeds, the use of the feeds at the farm, transport at all stages, and the production and use of energy resources . The assessment revealed that the use of fishery resources (such as biotic resource use) and nutrient emissions at the farm (such as eutrophication potential) contribute most to the potential environmental impacts of salmonid aquafeeds . Improvements in feed composition and management practices seem to be the best ways for improving the environmental profile of aquafeeds.

Rev Environ Contam Toxicol, 2003, 179, 1 - 36
Physical, chemical, and biological changes in the Gulf of Gdańsk ecosystem (southern Baltic sea); Kot-Wasik A et al.; This review presents the present state of knowledge of the physical, chemical, and biological changes in waters of the Gulf of Gdansk (Baltic Sea) . The general characteristics of the Baltic Sea and the Gulf of Gdansk with brief description of changes in the ecosystem are included . Among meteorological parameters describing climate in the coastal zone, water temperature changes together with considerations of precipitation and sea level are presented . It has been confirmed that the sea level rise over the past 40 yr was very distinct . Throughout the past 30 yr an evident increase in eutrophication has been observed . Therefore, changes in salinity, oxygen content, and nutrient fluctuations with special attention paid to variability in silicate, nitrate, and phosphate concentrations in the water layer are presented . Also, discussion on the presence of toxic pollutants, such as heavy metals, PCBs, PAHs, and some pesticides, in the water body of the Gulf of Gdansk has been included . Because of their ability to bioaccumulate and biomagnify in living organisms, these substances are of crucial importance for future marine life in the Gulf of Gdansk . Finally, biological conditions of the coastal waters of the Gulf of Gdansk were discussed . Data show that the ecosystem structure of the Gulf of Gdansk has undergone tremendous changes . The species pattern has changed significantly--many species have disappeared and others have become dominant.

Environ Sci Technol, 2004 Aug 1, 38(15), 4165 - 8
Chlorophyll fluorescence imaging of individual algal cells: effects of herbicide on Spirogyra distenta at different growth stages; Endo R et al.; Serious environmental degradation of aquatic ecosystems has been caused by eutrophication and by pollutants such as herbicides . Therefore, measurement of in situ algal photosynthetic activity is important for environmental monitoring . With ordinary nonimaging fluorometers, algal chlorophyll fluorescence can be measured easily, but heterogeneity within samples cannot be detected . Effects of a herbicide preparation containing 3-(3,4-dichlorophenyl)-1,1 -dimethylurea (DCMU) on photosynthetic activity at different growth stages of Spirogyra distenta were investigated by using a computer-aided microscopic imaging system for chlorophyll afluorescence . Photosystem II photochemical yield (phiPSII) images were used to diagnose photosynthetic activity of spiral filate chloroplasts in algal cells . The herbicide treatment caused a stronger decline in phiPSII values in younger than in mature algae cells . This result indicated that heterogeneity within algal samples should be considered when algae are used for environmental monitoring . Thus, measurement of chlorophyll fluorescence from young and mature chloroplasts with a microscopic imaging system makes it possible to improve the sensitivity for monitoring the environmental degradation of aquatic ecosystems.

Mar Pollut Bull, 2004 Aug, 49(4), 344 - 53
Nutrient enrichment caused by in situ fish farms at Eilat, Red Sea is detrimental to coral reproduction; Loya Y et al.; Recent studies report conflicting results concerning the effects of eutrophication on coral reproduction . The present study examines reproductive effort in the brooding coral Stylophora pistillata exposed to chronic eutrophication caused by in situ fish cages (FC) in the northern Gulf of Eilat (Aqaba) . Histological studies of 20 S . pistillata colonies transplanted to each of two study sites, one close to the nutrient enriched FC site and the other at a reference site (IUI), 8 km southwest of the FC site, show that, overall, corals from the FC site have a significantly higher percentage of polyps containing oocytes and testes than corals from the IUI site . However, average oocyte size and the percentage of oocytes reaching the size at which fertilization occurs (i.e., >200 microm) were both significantly greater in colonies at the IUI site compared to the FC site . As the reproductive season progressed, colonies at the IUI site exhibited a decrease in the percentage of polyps containing oocytes, concomitant with an increase in the number of polyps containing planulae, indicating successful development of oocytes into planulae . In contrast, in colonies at the FC site oocyte numbers were greatest at the end of the reproductive season, and overall, numbers of planulae were significantly lower compared with the IUI colonies, suggesting relative failure of oocyte maturation, fertilization and ensuing larval development . The significantly higher lipid content found during the reproduction season in IUI colonies compared with FC colonies corroborates this assertion . This data strongly suggest that nutrients released from the fish farms have adverse effects on successful production of larvae of S . pistillata . In view of the recent severe deterioration of the coral reefs of Eilat and their present critical state of health, the only chance for their renewal is the use of immediate, prudent and rational protection measures against all man-made perturbations.

Mar Pollut Bull, 2004 Sep, 49(5-6), 496 - 503
Distribution and characteristics of suspended particulate matter in a heavily eutrophic estuary, Tokyo Bay, Japan; Suzumura M et al.; Bulk suspended particulate matter (SPM), chlorophyll a (Chl a), ignition loss, particulate organic carbon (POC), organic nitrogen, inorganic phosphorus (PIP), and organic phosphorus were investigated in the heavily eutrophic Arakawa River estuary, Japan . Chl a was high (approximately 35 microg l(-1)) in summer and low (approximately 6.7 microg l(-1)) in winter and autumn . POC from living phytoplankton accounted for approximately 34% and approximately 70% of total POC during low- and high-biomass seasons, respectively . During the low-biomass season, detrital POC distribution was conservative, and less reactive, land-derived materials mainly composed particulate organic materials (POM), but complex mixing of land-derived POM and autochthonous planktonic detritus caused nonconservative detrital POC behavior during the high-biomass season . PIP concentration in SPM decreased with increasing salinity, likely by desorption of soluble orthophosphate (ortho-P) . The ortho-P released from SPM, 56% of the ortho-P input from the Arakawa River to the bay, was a significant potential source of biologically available phosphorus causing eutrophication of coastal environments .

J Anim Sci, 2004 Jul, 82(7), 2115 - 22
Environmental impacts of the Japanese beef-fattening system with different feeding lengths as evaluated by a life-cycle assessment method; Ogino A et al.; The objectives of this study were to evaluate the environmental impacts of a beef-fattening system using the life-cycle assessment (LCA) method and to investigate the effects of feeding length on the LCA results . The functional unit was defined as one animal, and the stages associated with the beef-fattening life cycle, such as feed (concentrate and rough-age) production, feed transport, animal management, animal body (i.e., biological activity of cattle), and the treatment of cattle wastes, were included in the system boundary . Our results suggest that enteric or gut CH4 emissions of cattle were the major source in the impact category of global warming (2,851 kg of CO2 equivalents), whereas NH3 emissions from cattle waste were the major source in the impact categories of acidification (35.1 kg of SO2 equivalents) and eutrophication (6.16 kg of PO4 equivalents) . Feed production also contributed a great deal to all categories . A shorter feeding length resulted in lower environmental impacts in all the environmental impact categories examined in the current study, such as global warming and acidification, although there was a difference in effect of reducing environmental impacts among the categories.

Environ Toxicol Chem, 2004 Mar, 23(3), 682 - 90
Silver uptake by a marine diatom and its transfer to the coastal copepod Acartia spinicauda; Xu Y et al.; Silver (Ag) is an important metal contaminant in many coastal waters and often is accompanied by high nutrient concentrations in the effluent outfall . The biological uptake of Ag by the marine diatom Thalassiosira pseudonana at various levels of nitrate, ammonium, and phosphate was examined under different growth conditions of the cells . The biological uptake of Ag increased significantly with increasing concentrations of nitrate, ammonium, and phosphate, presumably because of the increase in algal growth rate or increasing sulfur-containing ligands available for Ag transport . The calculated Ag uptake rate constants increased by 3 to 16 times with increasing nitrate and ammonium concentration from 5.88 microM to 176 microM . The assimilation efficiency (AE) of Ag by the coastal copepod Acartia spinicauda was quantified under different ecological and chemical conditions of the diatom prey . The Ag AEs were in the range of 3 to 23%, and increased with decreasing diatom food concentrations or when the diatoms were grown at a lower nutrient level . Significant correlations were demonstrated between the AE and the distribution of Ag in the diatom's cytoplasm, the Ag concentration factor in the diatoms, Ag retention in the particles during the feeding period, and the Ag gut passage time in the copepods . Desorption within the copepod's gut appears to play a critical role in Ag assimilation and partially accounts for the variability of Ag AEs under different food and geochemical conditions . Our study highlights that several geochemical and physiological processes all significantly affect Ag trophic transfer in marine copepods . Given the dependence of Ag transfer on its concentration in ingested particles and food concentration, dietary uptake of Ag is probably variable in natural environments . The influence of eutrophication on Ag trophic transfer is dependent on the degree to which each kinetic parameter is affected by nutrient enrichments.

J Environ Sci (China), 2004, 16(3), 358 - 63
Effect of nitrogen and phosphorus on the water quality in the Three Gorges Reservoir Area during and after its construction; Liu H et al.; A survey concerning the concentration of the nutrients in the Three Gorges Reservoir Area was carried out . This paper presents the parameters(NO3- -N, NO2- -N, Kjeldahl-N, non-ionic ammonia, P-PO4 and TP) determined at 16 sampling sites from 1997 to 1999 . The dominant soluble nitrogen form was NO3- -N followed by Kjeldahl-N, NO1- -N and non-ionic ammonia . Mean values of NO3- -N, NO2- -N, Kjeldahl-N and non-ionic ammonia ranged from 0.50 to 2.37 mg/L, 0.022 to 0.084 mg/L, 0.33 to 0.99 mg/L and 0.007 to 0.092 mg/L respectively . Mean values of P-PO4 at most sampling sites were higher than 0.1 mg/L for subject to eutrophication . The major factors influencing the concentrations of N and P might be agricultural runoff, municipal and industrial effluents . In addition, 6 kinds of soil were sampled at the area where would inundated after the dam completed . Two approaches were adopted to simulate the N and P release from the inundated soils . The results showed that the soils would release nitrogen and phosphorus to the overlying water when the soils were inundated . The characteristics of soil affected the equilibrium concentrations of N and P between the soil and the overlying water.

J Environ Biol, 2003 Jul, 24(3), 331 - 7
Heavy metal pollution in various canals originating from river Yamuna in Haryana; Kaushik A et al.; Heavy metal pollution due to Fe, Ni, Pb, Cd, Co and Zn in the water of major canals originating from the river Yamuna in Haryana was studied . All these metals except Zn were found to be present in the Western Yamuna Canal (WYC) exceeding the maximum permissible limits . In the Sunder branch (SB), the heavy metal concentration was relatively more . Concentrations of the metals were, however, relatively less in the highly eutrophicated waters of Agra canal and Gurgaon canal as compared to that in WYC but Fe concentration were much higher . Except Zn and Ni the metal concentrations exceeded the standard permissible limits in these canals also.

J Environ Qual, 2004 Jul-Aug, 33(4), 1452 - 63
Relationship between soil test phosphorus and phosphorus in runoff: effects of soil series variability; Schroeder PD et al.; Phosphorus loss in runoff from agricultural fields has been identified as an important contributor to eutrophication . The objective of this research was to determine the relationship between phosphorus (P) in runoff from a benchmark soil (Cecil sandy loam; fine, kaolinitic, thermic Typic Kanhapludult) and Mehlich III-, deionized water-, and Fe(2)O(3)-extractable soil P, and degree of phosphorus saturation (DPS) . Additionally, the value of including other soil properties in P loss prediction equations was evaluated . Simulated rainfall was applied (75 mm h(-1)) to 54 1-m(2) plots installed on six fields with different soil test phosphorus (STP) levels . Runoff was collected in its entirety for 30 min and analyzed for total P and dissolved reactive phosphorus (DRP) . Soil samples were collected from 0- to 2-, 0- to 5-, and 0- to 10-cm depths . The strongest correlation for total P and DRP occurred with DPS (r(2) = 0.72) . Normalizing DRP by runoff depth resulted in improved correlation with deionized water-extractable P for the 0- to 10-cm sampling depth (r(2) = 0.81) . The STP levels were not different among sampling depths and analysis of the regression equations revealed that soil sampling depth had no effect on the relationship between STP and P in runoff . For all forms of P in runoff and STP measures, the relationship between STP and runoff P was much stronger when the data were split into groups based on the ratio of oxalate-extractable Fe to Al . For all forms of P in runoff and all STP methods, R(2) increased with the inclusion of oxalate-extractable Al and Fe in the regression equation . The results of this study indicate that inclusion of site-specific information about soil Al and Fe content can improve the relationship between STP and runoff P.

Mar Pollut Bull, 2004 Aug, 49(3), 206 - 19
Plankton of the Baltic estuarine ecosystems with emphasis on Neva Estuary: a review of present knowledge and research perspectives; Telesh IV; Different levels of eutrophication and pollution in the Baltic coastal waters in general, and in estuaries particularly define variations in the buffering capacity of ecosystems of these important filter zones between rivers and the adjacent Baltic Proper . Phyto- and zooplankton in the estuaries form important components of the pelagic food webs that participate in producing and structuring the matter, energy, and information fluxes in the ecosystems . Due to salinity gradients, estuaries provide a large variety of aquatic habitats for native populations of marine, brackish and fresh water plankton species . Non-indigenous planktonic species that expand their bio-geographical range and invade the Baltic coastal ecosystems also find favourable environments, establish permanent populations there, and impact aboriginal ecosystems . The dynamics of abundance, species diversity, population structure, productivity of planktonic communities, and peculiarities of trophic interactions in different Baltic estuaries are influenced by a number of common environmental factors . Being measured on the unified basis and monitored, changes (or stability) of structural and functional parameters of plankton communities can serve as indicators of alterations to the ecosystems . Comparative analyses and quantitative estimates of long-term changes in phyto- and zooplankton can contribute to evaluation of functional response of Baltic coastal ecosystems to anthropogenic stress . Both theoretical (modeling) and empirical studies of interactions within plankton communities aimed at the assessment of the role of planktonic organisms in water quality regulation, and applicability of these data for the evaluation of the status of ecosystems and their management can be considered as major goals for the future investigations in Baltic estuaries.

Mar Pollut Bull, 2004 Aug, 49(3), 186 - 95
Eutrophication in the Polish coastal zone: the past, present status and future scenarios; Lysiak-Pastuszak E et al.; In the Baltic Sea eutrophication processes have accelerated in the past 50 years of the 20th century and presently there exists a major ecological problem for this sea . The Polish coastal zone of the southern Baltic Sea is the recipient of riverine inputs from two major sources, namely the Odra and Vistula, as well as a number of smaller rivers along the central coast . Hence, the entire coastal zone remains under severe anthropogenic pressure . The variability of nutrient concentrations, especially the winter nutrient pool in the euphotic zone, summer level of total nitrogen and total phosphorus, together with such eutrophication indicators as water oversaturation with oxygen and the summer oxygen minimum, were analysed in the data time series 1959-2001 . The temporal trends were investigated using linear regression and the non-parametric Whirsch test . The future characteristics of the Baltic Sea are discussed taking into account the development of driving forces.

Mar Pollut Bull, 2004 Aug, 49(3), 148 - 53
Chlorophyll a and its derivatives in sediments of the Odra estuary as a measure of its eutrophication; Kowalewska G et al.; Chlorophyll a and its selected derivatives, as well as chlorophylls b and c have been determined in samples of recent (0-10 cm) sediments, collected at 30 stations in the Szczecin Lagoon, Pomeranian Bay and the Bornholm Deep . Samples were retrieved in different seasons between 1992 and 2001, including the time before and after the great flood of July 1997 . Regarding the content of chlorophyll a and its derivatives in sediments, the Szczecin Lagoon may be classified as permanently eutrophic and the Pomeranian Bay and Bornholm Deep as mesotrophic . A lack of correlation between chlorophylls b, c and chlorophyll a indicated that intensive blooms of cyanobacteria occur in the Szczecin Lagoon, which is a characteristic of eutrophic zones . The chlorin a results are related to selected parameters characterizing the aquatic environment . The values for nutrients, salinity and temperature in near-bottom waters, as well as granulometry and organic carbon in the sediments verify the above conclusions.

J Environ Sci Health A Tox Hazard Subst Environ Eng, 2004 Jun, 39(6), 1455 - 77
Eutrophication modeling in Shihmen Reservoir, Taiwan; Wu RS et al.; Based on the measured data, including total phosphorus, chlorophyll a, and Secchi disk depth, the Shihmen Reservoir in the state of mesotrophic to eutrophic . A two-dimensional, laterally averaged, finite-difference hydrodynamic, and water quality model was applied to simulate water quality conditions in the reservoir to determine appropriate strategies for the management of water quality . Data collected in the field for a two-year period were utilized to calibrate and verify the model . The model calibration and verification were achieved with water surface elevation, temperature, and water quality constituents such as nutrients, dissolved oxygen, and chlorophyll a . Then the model was used to simulate chlorophyll a concentrations under several scenarios corresponding to various waste load reduction ratios . A 90% reduction of nutrient loadings will upgrade the existing eutrophic/mesotrophic conditions to oligotrophic condition in both 2001 and 2002, exception January in 2001 . The modeling effort had yielded valuable information that can be used by decision maker for the evaluation of different management strategies of reduction of nutrients coming from the catchment area.

Mar Pollut Bull, 2004 Jul, 49(1-2), 89 - 92
Reactive sulfides relationship with metals in sediments from an eutrophicated estuary in Southeast Brazil; Machado W et al.; The potential association of acid-volatile sulfides (AVS) and reactive (HCl soluble) Fe with the distribution of reactive trace metals (Cu, Cd, Ni, Pb and Zn) was investigated in sediment cores collected in the Iguacu river estuarine system (Guanabara bay, Brazil), within the river (core R) and the bay (core B) areas . Moderate to extremely high AVS concentrations (33-314 micromol g(-1)) were found in the rapidly-accumulated sediments of this eutrophicated estuary . AVS showed significant correlations with Fe, Ni and Pb in core B, whereas no correlation between AVS and metals was observed in core R . Results suggest that the AVS:Fe molar ratio may often reflect the diagenetic conditions controlling the distribution of Cd and Cu in core B better than AVS and Fe levels themselves . A shift in the biogeochemical controls of metal distribution from the river to the open bay sediments is suggested, with a greater association of most metals with AVS and Fe in bay sediments.

Environ Pollut, 2004 Sep, 131(2), 313 - 21
Performance of a narrow buffer strip in abating agricultural pollutants in the shallow subsurface water flux; Borin M et al.; The performance of a narrow buffer strip in abating dissolved P, electrical conductivity and herbicides (terbuthylazine, alachlor, nicosulfuron, pendimethalin, linuron) in subsurface water coming from cropland was tested in an experiment carried out on the low plains of the Veneto Region (NE Italy) . The experiment lasted from December 1997 to June 1999, monitoring subsurface water quality entering and exiting a buffer composed of a grass strip (5 m wide) and 1 m wide row of trees . Dissolved phosphorus concentrations were reduced by almost 100% passing through the buffer and in most cases exiting water satisfied the limit for avoiding eutrophication . A positive effect was also detected on ECW (reduced by 20%), while pH was not significantly altered . Herbicide concentration abatement varied between 60 and 90%, depending on the chemical and the time elapsed since application.

J Environ Qual, 2004 May-Jun, 33(3), 1124 - 32
Phosphorus removal in a wetland constructed on former arable land; Liikanen A et al.; Phosphorus in surface runoff water may cause eutrophication of recipient water . This study clarifies the mechanisms of P removal in the wetland of Hovi, Finland, constructed on arable land in 1998 . Before the construction, the surface soil (removed in the construction) and subsoil (the current wetland bottom) were analyzed for Al and Fe oxides (Al(ox) and Fe(ox)) reactive in P sorption, and for the distribution of P between various pools as well as for P exchange properties . Retention of P from runoff water within the wetland was studied from 1999 to 2001 in situ and factors affecting the P removal (O2 availability and P concentration in water) were investigated in a laboratory microcosm . The processes taking place in the wetland diminished by 68% the total P load and by 49% the dissolved reactive P load . Desorption-sorption tests indicated that without removal of the surface soil, there would have been a risk of the wetland being a source of P, since the equilibrium P concentration of the soil removed was high compared with the mean P concentration of the inflowing water . The subsoil contained less P and high amounts of reactive oxides, which could bind P . Evidently, the P sorption by Al(ox) played an important role in a first phase removal of P, since the wetland retained P efficiently even under anoxic conditions, where Fe tends to be reduced . Fine-textured, mineral soil on the bottom of the wetland (subsoil of the former arable land) seemed to be very efficient in retaining P from agricultural runoff.

J Environ Qual, 2004 May-Jun, 33(3), 1048 - 54
Reducing phosphorus runoff from swine manure with dietary phytase and aluminum chloride; Smith DR et al.; Phosphorus (P) runoff from fields fertilized with swine (Sus scrofa) manure has been implicated in eutrophication . Dietary modification and manure amendments have been identified as best management practices to reduce P runoff from manure . This study was conducted to compare the effects of dietary modification and aluminum chloride (AlCl3) manure amendments on reducing P in swine manure and runoff . Twenty-four pens of nursery swine were fed either a normal diet or a phytase-amended diet . Each pen was connected to a separate manure pit, which was treated with AlCl3 to give final concentrations in the liquid manure of 0 (control), 0.25, 0.50, or 0.75% (v/v) . Manure was collected and applied to plots cropped with tall fescue (Festuca arundinacea Schreb.), and simulated rainfall was applied at 50 mm h(-1), sufficient to generate a minimum of 30 min of continuous runoff . Samples of manure and runoff were analyzed for P and Al concentrations . Phytase reduced manure soluble reactive phosphorus (SRP) by 17%, while AlCl3 reduced manure SRP by as much as 73% compared with normal manure . Phosphorus runoff was reduced from 5.7 to 2.6 mg P L(-1) (a 53% reduction) using AlCl3 . The mean SRP concentration in runoff from phytase diets without AlCl3 was 7.1 mg P L(-1) during the first rainfall simulation . When phytase and AlCl3 were used together, both manure SRP and P runoff were reduced more than if either treatment were used without the benefit of the other . Use of AlCl3 did not increase soluble Al in manure or Al lost in runoff . Results from this study indicate that producers should use dietary manipulation with phytase and AlCl3 manure amendments to reduce potential P losses from fields fertilized with swine manure.

Environ Pollut, 2004 Sep, 131(1), 93 - 105
Comparison of throughfall and soil solution chemistry between a high-density Corsican pine stand and a naturally regenerated silver birch stand; De Schrijver A et al.; In Flanders, critical loads for acidification and eutrophication are exceeded in the majority of the forest stands, and many previously nitrogen limited forest ecosystems have become nitrogen saturated . The present study investigates whether a naturally regenerated stand of silver birch (Betula pendula Roth) contributes less to the acidification and eutrophication of the forest soil than a high-density plantation of Corsican pine (Pinus nigra ssp . laricio Maire) . Throughfall deposition of inorganic nitrogen was about 3.5 times higher in the Corsican pine stand than in the birch stand . Potassium throughfall deposition was significantly higher under birch due to higher canopy leaching . Magnesium throughfall deposition was significantly higher under the pine canopy due to higher dry deposition . The lower nitrogen throughfall deposition in the birch stand was reflected in a 60% lower nitrate percolation at 1m depth compared with pine . Nitrate soil percolation is linked to losses of aluminium and base cations.

Water Res, 2004 Jun, 38(11), 2764 - 74
Bayesian methods for regional-scale eutrophication models; Lamon EC 3rd et al.; We demonstrate a Bayesian classification and regression tree (CART) approach to link multiple environmental stressors to biological responses and quantify uncertainty in model predictions . Such an approach can: (1) report prediction uncertainty, (2) be consistent with the amount of data available and (3) be flexible enough to permit updates and improvements . Tree-based methods are a flexible approach useful for variable subset selection and when the analyst suspects global nonlinearity and cannot (or does not want to) specify the functional form of possible interactions a priori . We use the US EPA National Eutrophication Survey data to fit three models demonstrating the methods and to highlight important differences arising from slightly different model specifications . The Bayesian approach offers many advantages, including the estimation of the value of new information and proper probability distributions on the variable of interest as an output, which can be directly used in risk assessment or decision-making.

Sci Total Environ, 2004 Jul 26, 328(1-3), 207 - 18
The impact of surface water exchange on the nutrient and particle dynamics in side-arms along the River Danube, Austria; Hein T et al.; Results of two monitoring programs obtained in the free-flowing section of the Danube downstream of Vienna were used to evaluate the effects of river restoration designed to increase surface water inputs into side-arms . Functional descriptors like hydrochemical parameters and plankton react immediately to restored hydrological conditions and offer the opportunity to elucidate the hydrological control on organic processing as an important ecosystem function in fluvial landscapes . Two hydraulic parameters were estimated and linked to basic ecological properties . The level of hydrological connectivity was defined as the average annual duration (days per year) of upstream surface connection and can be used as a 'simple to estimate' parameter within the planning phase . Water age, an adapted measure of residence time based on more detailed information, allow description of the temporal development in side-arms . Greater hydrological connectivity leads to lower conductivity levels and increased nutrient concentrations due to the shift of the dominating source to river water . The contribution of river flow is indicated by higher suspended solid concentrations in side-arms than disconnected water bodies . The phytoplankton biomass shows the highest mean values at a duration of integration of 1 month a(-1) and decrease with increasing connectivity . The relationships point to a more 'main channel like' hydrochemical situation in the side-arms, with a medium level of phytoplankton biomass and increased autochthonous carbon export . No evidence of eutrophication was found due to the shift of the side-arm from an organic matter sink to a source . On a more detailed level, water age demonstrates the temporal patterns of riverine input, the development of plankton production and the shift between hydrological and biological control of phytoplankton vs . riverine flow in a side-arm . The hydrologic parameters were useful predictors for evaluating the effects of restoration measures in river floodplain systems .

Water Sci Technol, 2004, 49(7), 189 - 97
Drainage basin security of hazardous chemical fluxe in the Yodo River basin; Matsui S; The Yodo River basin consists of three major tributary basins (and other small river basins) namely Uji, Katsura and Kizu, which overlap respectively Shiga, Kvoto and Nara prefectures' administrative areas . Lake Biwa, the largest lake in Japan, drains water through the Uji river . The water quality of the lake, in terms of BOD, continuously improved over the last decade . However, the quality in terms of COD did not show any improvement in spite of a large amount of infrastructure finance being introduced . Eutrophication of the lake still continues, showing no improvement in the nitrogen concentration level . Non-point as well as point source control is not strong enough . There is a gap between BOD and COD evaluations of the lake water quality . Hazardous chemical fluxes are estimated based upon PRTR reports of Japan (2001) . PCBs are still discharged into the lake, although the report of Shiga Prefecture showed zero discharge . Dace fish monitoring clearly showed that PCB contamination of the fish had not changed since the 1980s in spite of a ban on use and production of PCBs in the 1970s . There is still leakage of PCBs into the lake . The major exposure of dioxins to Japanese is fish rather than meat and eggs . The risk of water contamination must take into consideration not only drinking water safety but also ecological magnification of food chains in water . The ecological health aspect of hazardous chemicals is also important, such as organotins with imposex of sea snails . Finally, public participation in hazardous chemical management is very important using the method of risk communication based upon the annual report of PRTR in Japan.

Rev Biol Trop, 2003 Jun, 51(2), 381 - 90
{Limnology of high mountain tropical lake, in Ecuador: characteristics of sediments and rate of sedimentation}; Gunkel G; Equatorial high mountain lakes are a special type of lake occurring mainly in the South American Andes as well as in Central Africa and Asia . They occur at altitudes of a few thousand meters above sea level and are cold-water lakes (< 20 degrees C) . Relatively little is known about them . A long-term limnological study was therefore undertaken at Lake San Pablo, Ecuador, to analyze the basic limnological processes of the lake, which has a tendency for eutrophication . Sediment quality of San Pablo Lake is given under consideration of horizontal and vertical distribution using sediment cores . Significance of sediments for eutrophication process of lakes is demonstrated using phosphorus concentration of sediments as well as the phosphorus retention capacity of the sediments by ratio Fe/P . Dating of the sediments is done using 137Cs and 210Pb, but the activity of 137Cs in the sediment was very low nearly at the detection level . Sedimentation rate is determined to be 3.5 mm/year and the sediment cores represent about 110 years . P concentration of the sediments is high (approximately 5 g/kg dry substance), and P retention capacity by Fe is insufficient (Fe/P = 4) . The sediment quality did not change significantly during the past decades, and the trophic state of San Pablo Lake was already less or more eutrophic 110 years ago . The contamination of the lake sediments by heavy metals is insignificant.

Rev Biol Trop, 2003 Mar, 51(1), 99 - 106
On the phytoplankton of Awba reservoir, Ibadan, Nigeria; Akin-Oriola GA; The physico-chemical characteristics and phytoplankton of Awba reservoir in the University of Ibadan, Nigeria, were monitored to determine the impact of eutrophication on phytoplankton composition . The principal component analysis identified three major components influencing the physicochemistry of the water, namely trace metals, dissolved oxygen and ionic composition . Comparative analysis with a previous study showed a phenomenal increase in zinc, copper and iron levels over a 10-year period . Furthermore, the ferruginous nature of the soil contributed to the high levels of iron which exceeded the World Health Organization Standards for drinking water quality . The most abundant phytoplankton species was Microcystis aeruginosa which has been implicated in toxic blooms in freshwaters . The conditions favouring cyanophyte blooms and their implications are discussed.

Environ Pollut, 2004 Jul, 130(2), 187 - 98
Polybrominated diphenyl ethers (PBDEs) and their methoxylated derivatives in pike from Swedish waters with emphasis on temporal trends, 1967-2000; Kierkegaard A et al.; Temporal trends of five tetra- to hexabromodiphenyl ethers {BDE47, BDE99, BDE100, BDE153 and BDE154) and two methoxy-tetraBDEs {6-methoxy-2,2',4,4'- tetraBDE (6-MeO-BDE47) and 2'-methoxy-2,3',4,5'- tetraBDE (2'-MeO-BDE68)} in pike from Lake Bolmen for the years 1967-2000, are presented . All BDE congeners show increasing trends up to the mid-1980s (Sigma5PBDE from 60 to 1600 pg/g wet weight in 1989, i.e . a more than 25-fold increase), and then decrease or level off . The decreasing trends of PBDEs after the 1980s were considerably slower in the present study than was found in a study of an environmental matrix from the Baltic Proper covering the same time period . This difference suggests local sources near Lake Bolmen . The MeO-BDEs show initially decreasing concentrations, which for 6-MeO-BDE47 continues until the early 1990s . The concentrations of 6-MeO-BDE47 in herring from five locations along the Swedish coast increased from south to north in the Baltic Sea . No correlation between the concentrations of the BDE congeners and the MeO-BDEs was observed, indicating sources other than PBDEs for these compounds . The presence of MeO-BDEs in fish from lakes with different characteristics suggests a natural production not favoured by eutrophication, or dependent on sampling season and geographical location.

Environ Manage, 2004 Jul, 34(1), 125 - 39 Epub 2004 May 13.
Observed winter warming of the Chesapeake Bay estuary (1949-2002): implications for ecosystem management; Preston BL; A large number of studies have documented 20th century climate variability and change at the global, hemispheric, and regional levels . However, understanding the implications of climate change for environmental management necessitates information at the level of the ecosystem . Historical monitoring data from the Chesapeake Bay estuary were used to identify temporal patterns of estuarine temperature anomalies in the surface (</=1 m) and subsurface (>/=15 m) between 1949 and 2002 . Data indicated a trend in surface and subsurface warming of +0.16 degrees C and +0.21 degrees C per decade, respectively, driven by warming during winter and spring . These trends suggest warming of the estuary since the mid-20th century of approximately 0.8-1.1 degrees C . Estuarine temperatures correlated well with other independent data records for sea surface and surface air temperatures in the region and to a lesser extent, the northern hemisphere . Gross long-term temperature variability in the estuary was consistent with North Atlantic climate variability associated with the prolonged positive North Atlantic Oscillation/Arctic Oscillation and increased anthropogenic radiative forcing, although localized environmental drivers likely are important as well . A simple spatial analysis revealed strong seasonal latitudinal and longitudinal gradients in estuarine temperature as well as a north-south gradient in long-term temperature trends . Continued warming of the estuary will have important implications for ecosystem structure and function as well as attempts to manage existing challenges such as eutrophication and benthic hypoxia . However, such management efforts must be cognizant of the effects of various climate and nonclimate drivers of environmental variability and change operating over different spatial and temporal scales.

Oecologia . 2004 May 14; {Epub ahead of print}
Genetic and environmental variation in performance of a marine isopod: effects of eutrophication; Hemmi A et al.; Environmental variation in food resources modifies performance of herbivores, in addition to genetic variation and maternal effects . In marine benthic habitats, eutrophication may modify herbivores' diets by changing host species composition or nutritional quality of algae for herbivores . We studied experimentally the effects of diet breadth and nutrient availability for the host algae on fitness components of the herbivorous isopod Idotea baltica . We fed the adult isopods with the brown algae Fucus vesiculosus and Pilayella littoralis and juveniles with the green alga Cladophora glomerata . By using half-sib families, we were able to separate the genetic, environmental and maternal effects on intermolt duration and size of the juveniles . The mothers confined to the diet consisting of both Fucus and Pilayella grew better and produced larger egg mass than those having consumed Fucus alone . Nutrient enhancement of algae did not influence the performance of the adult herbivores . However, the juveniles achieved twice the weight as well as shorter intermolt duration when consuming nutrient-treated C . glomerata . Mother's nutrition, either nutrient enrichment of her food algae or diet breadth, did not affect juvenile survival or growth as such, but we found evidence that the broader diet consumed by the mother mediated offspring performance by further accelerating growth rate of the offspring that fed on nutrient-treated alga . Intermolt duration was a highly heritable trait, but size showed very low heritability . Instead, maternal effects on size were substantial, suggesting that differences among mothers in their egg-provisioning ability strongly affect weight gain of their offspring . A high amount of additive genetic variance in intermolt duration implies potential for quick evolutionary responses in the growth schedule in the face of changes in the selective environment . We conclude that eutrophication, in addition to improving growth and reproduction of I . baltica by enhancing food quality and by providing opportunity for broader, more profitable diets, may act as a selective agent on life-history traits . Eutrophication of coastal waters is thus likely to reflect in herbivore density, population dynamics and eventually, grazing pressure of littoral macroalgae.

Environ Pollut, 1998, 99(2), 177 - 98
Temporal trends of organochlorines in Northern Europe, 1967-1995 . Relation to global fractionation, leakage from sediments and international measures; Bignert A et al.; The time trend monitoring of organochlorine pollution was carried out in Sweden since the late 1960s . This report presents data on concentrations of DDT, PCB, HCHs and HCB in biota samples collected and analysed annually . All the matrices and compounds studied show a significant decrease over time . The data cover severely polluted Swedish marine and fresh water in southern Sweden as well as locally unpolluted waters in remote northern Arctic regions of Sweden . A total of 13 time series representing different locations and species are presented for the different pollutants . The period studied covers the time when pollution was serious as well as the time of recovery . All monitoring activities were carried out at the same laboratories over the entire study period, which means that comparability over time is good in the sets of data presented . The various time trends show a convincing agreement with trends and annual change over time, although the concentrations differ between the species and locations investigated, the highest concentrations being in the south . Since the annual changes are normally similar regardless of locations and species, spatial variations in concentrations remain over time, although concentrations are lower today . The onset of changes in concentrations over time can be related to international measures or other circumstances that lowered releases into the environment . Similarities in the annual changes, as well as the time when changes began, are discussed with respect to suggested hypotheses on the fate of the investigated organochlorines . It was not possible to verify that the oxygenation of anoxic sediments mobilised old pollution in Baltic sediments . Neither was it possible to conclude that eutrophication has caused a measurable effect on the rate and timing of the decreases . Finally, long-range transport to Arctic regions seems to be due more to a one step transport than to the 'Grass-hopper' effect . The comprehensive database used, clearly shows how important it is to have datasets big enough to describe between-year variation before attempting to evaluate the time trend . In addition, if between-year variation is not known, it is then also difficult to evaluate spatial variation on the basis of single year observations.

Environ Pollut, 1999, 100(1-3), 223 - 40
The evolution of mass balance models of persistent organic pollutant fate in the environment; Wania F et al.; Current approaches to modelling the fate of persistent organic pollutants (POPs) in the environment have evolved in response to four dominant characteristics of these substances; namely: (1) the presence of POPs in virtually all environmental phases and the ease with which they move from one to the other requires multi-compartmental modelling . Describing transport across phase boundaries becomes as, or even more, important as quantifying transport within the phases; (2) POPs may persist in the environment for many decades . For chemicals that 'have time', concepts such as equilibrium partitioning and steady-state become more important than for short-lived substances whose fate is more controlled by the rates of transformation; (3) measuring POPs is difficult and expensive and observed concentrations of POPs are not available in high spatial or temporal resolution . Consequently, high resolution tends not to be a high priority in POP models; and (4) detrimental effects of POPs often manifest themselves in top predators, which has led to a focus on modelling biotic uptake and transfer within food chains . The task of building a POPs model is viewed as combining the four 'building blocks' of partitioning, transport, transformation and source data with the help of the law of the conservation of mass . Process models, evaluative models, models of real local, regional and global fate, as well as biological uptake models are presented and references to numerous examples are provided . An attempt is made to forecast future directions in the field of POPs modelling . It is expected that modelling techniques that do not rely on quantitative emission estimates as well as approaches that take into account spatial, temporal and climatic variability as well as parameter uncertainty will increase in importance . Finally, the relationship between modelling POPs and models of other pollutant issues is addressed, as are potential interactions between POPs and pollutant issues such as eutrophication, acidification and global climate change.

Environ Pollut, 1999, 100(1-3), 179 - 96
Eutrophication: impacts of excess nutrient inputs on freshwater, marine, and terrestrial ecosystems; Smith VH et al.; In the mid-1800s, the agricultural chemist Justus von Liebig demonstrated strong positive relationships between soil nutrient supplies and the growth yields of terrestrial plants, and it has since been found that freshwater and marine plants are equally responsive to nutrient inputs . Anthropogenic inputs of nutrients to the Earth's surface and atmosphere have increased greatly during the past two centuries . This nutrient enrichment, or eutrophication, can lead to highly undesirable changes in ecosystem structure and function, however . In this paper we briefly review the process, the impacts, and the potential management of cultural eutrophication in freshwater, marine, and terrestrial ecosystems . We present two brief case studies (one freshwater and one marine) demonstrating that nutrient loading restriction is the essential cornerstone of aquatic eutrophication control . In addition, we present results of a preliminary statistical analysis that is consistent with the hypothesis that anthropogenic emissions of oxidized nitrogen could be influencing atmospheric levels of carbon dioxide via nitrogen stimulation of global primary production.

Environ Pollut, 2000 Aug, 109(2), 293 - 301
Gram stain index of a natural bacterial community at a nutrient gradient in the freshwater environment; Saida H et al.; Species succession of a natural bacterial community was indicated by the Gram stain index (GSI) using an experimental nutrient gradient in an oligotrophic pond created with an in situ gradostat . Various trophic conditions, ranging from eutrophic to mesotrophic, were formed experimentally with continuous inflow of sterile peptone solution in the gradostat, while the water mass outside the gradostat was oligotrophic . The GSI spectra of the natural bacterial populations show different profiles in accordance with the trophic level of the ambient water and the time progression of adaptation to different levels of eutrophication . Therefore, GSI can be used as a potential indicator of organic pollution in aquatic environments.

Environ Pollut, 1987, 46(3), 163 - 75
The effectiveness of lime-based amendments and bauxite residues at removing phosphorus from piggery effluent; Weaver DM et al.; Piggery effluent may contribute to the eutrophication of waterways, if it is not treated before disposal, because of high levels of phosphorus . Limes and red muds (a residue from bauxite refining) were used to remove phosphorus from piggery effluent (41 mg litre(-1) total P) . Lime-based amendments were more effective than the red muds at removing phosphorus when compared at the same liquid: solid ratios . Based on laboratory data, the cost of treating effluent increased rapidly as the final required phosphorus concentration decreased to less than 4 mg litre(-1) . Kiln dust was the cheapest amendment tested down to 2 mg litre(-1) . Hydrated lime was able to clarify and flocculate the effluent to 1 mg litre(-1) within 60 min . The re-useability of all limes may be determined by a simple pH test . Red mud could be used to remove phosphorus when its pH was lowered to 6.0-6.5 and it is used at liquid:solid ratios <20:1.

Environ Pollut, 1994, 83(1-2), 95 - 111
Agriculture's share in the emission of trace gases affecting the climate and some cause-oriented proposals for sufficiently reducing this share; Isermann K; This paper discusses agriculture's share in the world-wide emissions of climate-affecting gases and in the global warming potential (GWP) . Proposals also are presented to reduce these emissions adequately, using a cause-oriented approach . Largely due to the fertilization and cultivation of agriculture as well as the burning of biomass, agriculture has a very high share in the anthropogenic emissions of NH(3), N(2)O, CH(4) and CO at >95%, 81%, 70% and 52%, respectively, while its share in the NO(x) and CO(2) emissions is relatively small at 35% and 21% . The GWP of agriculture, based on annually {Formula: see text} tons of CO(2), approaches 63% of the GWP of the energy sector or 80% of the GWP of its CO(2) emissions . At 34% and 32%, respectively, the main originators in the GWP of agriculture would seem to be CO(2) (changing land use) and CH(4) (animal husbandry/rice cropping/biomass burning) followed at 15% by NO(2) (technical and biological N fixation/(cultivation and recultivation/biomass burning) and 10% and 9% by CO and NO(x) . The GWP of 3 German dairy cows corresponds with 13.2 tonnes CO(2) per year the GWP of two average German automobiles . However, the ozone-destroying effect of N(2)O and the climate-relevant effects of NH(3) are not yet included here . As with the therapy for other 'modern' boundary-crossing environmental damages, such as acidification or eutrophication, global climate change therapy likewise needs a therapy for the respective effects of reactive compounds of carbon, nitrogen, phosphorous, and sulfur also emitted by agriculture . Proposals for reducing these emissions within the agricultural sector include need-oriented plant, animal and human nutrition, more efficient external and internal nutrient recycling, the cessation of further clearing by burning, along with intensified afforestation mainly in the tropics, targeted measures to reduce nutrient losses/emissions, and measures for more efficient use of nutrients in plant, animal and human nutrition . These measures would at best result in reduced pollution of the global environment but not put it to an end . Decisive, therefore, is both the tolerable extent of mankind and its long-term sustainable way of life.

Environ Pollut, 1994, 84(3), 227 - 35
Phosphorus leaching in soils amended with piggery effluent or lime residues from effluent treatment; Weaver DM et al.; Phosphorus (P) in wastes from piggeries may contribute to the eutrophication of waterways if not disposed of appropriately . Phosphorus leaching, from three soils with different P sorption characteristics (two with low P retention and one with moderate P retention) when treated with piggery effluent (with or without struvite), was investigated using batch and leaching experiments . The leaching of P retained in soil from the application of struvite effluent was determined . In addition, P leaching from lime residues (resulting from the treatment of piggery effluent with lime to remove P) was determined in comparison to superphosphate when applied to the same three soils . Most P was leached from sandy soils with low P retention when effluent with or without struvite was applied . More than 100% of the filterable P applied in struvite effluent was leached in sandy soils with low P retention . Solid, inorganic forms of P (struvite) became soluble and potentially leachable at {Formula: see text} or were sorbed after dissolution if there were sufficient sorption sites . In sandy soils with low P retention, more than 39% of the total filterable P applied in recycled effluent (without struvite) was leached . Soil P increased mainly in surface layers after treatment with effluent . Sandy soils pre-treated with struvite effluent leached 40% of the P retained in the previous application . Phosphorus decreased in surface layers and increased at depth in the soil with moderate P retention after leaching the struvite effluent pre-treated soil with water . The soils capacity to adsorb P and the soil pH were the major soil properties that affected the rate and amount of P leaching, whereas the important characteristics of the effluent were pH, P concentration and the forms of P in the effluent . Phosphorus losses from soils amended with hydrated lime and lime kiln dust residues were much lower than losses from soils amended with superphosphate . Up to 92% of the P applied as superphosphate was leached from sandy soils with low P retention, whereas only up to 60% of the P applied in lime residues was leached . The P source contributing least to P leaching was the lime kiln dust residue . The amount of P leached depended on the water-soluble P content, netralising value and application rate of the P source, and the pH and P sorption capacity of the soil.

Environ Pollut, 1994, 86(1), 43 - 82
Effects of atmospheric ammonia on vegetation-A review; Fangmeier A et al.; Atmospheric ammonia does not only cause acute injuries at vegetation close to the source, but significantly contributes to large scale nitrogen eutrophication and acidification of ecosystems because the amount of sources is high and after conversion to ammonium it can reach remote areas by long-range atmospheric transport . Besides having acute toxic potential, NH(3) and NH(4)(+) (= NH(y)) may disturb vegetation by secondary metabolic changes due to increased NH(y) uptake and assimilation leading to higher susceptibility to abiotic (drought, frost) and biotic (pests) stress . Prevention of damage to natural and semi-natural ecosystems will only be achieved if NH(3) emissions are drastically reduced . In this paper, the current knowledge on NH(y) emission, deposition, and its effects on vegetation and ecosystems are reviewed . Critical levels and critical loads for nitrogen deposition are discussed.

Ambio, 2004 Feb, 33(1-2), 107 - 13
Ocean pollution from land-based sources: East China Sea, China; Li D et al.; The environment of East China Sea (ECS) has been faced by huge stresses from anthropogenic activities and population growth in the Yangtze River drainage basin and the areas along the coasts . Improper use of natural resources and short-term economic objectives have resulted in severe environmental degradation in a fairly short time frame and the degradation has now reached a level where the health and well being of the coastal populations are threatened . The main pollutants are inorganic nitrogen, phosphate, oil hydrocarbons, organic matters and heavy metals . Nutrients cause eutrophication of the coastal waters and the estuarine area and very often stimulate the occurrence of red tides . The environmental pollution of Yangtze River basin directly impact on the state of the marine environment in the ECS . The ecosystem stability is maintained by a steady water discharge from the river, that mixes with the marine salty water in the estuary, and the sediment loads from the river that balance ocean erosion in the delta and its adjacent coastal area . The large-scale water transfer and dam constructions in the Yangtze River basin will change this basis . For the ECS the challenge is to reverse the negative processes taking place and to restore ecosystem balance . The main challenge is to integrate socioeconomic and environmental decision making in order to promote sustainable development . A better understanding of the driving forces in society that cause these environmental pressures is required in order to overcome these obstacles . International cooperation may be an important contributor to the progress and in particular provide access to financial, technological, scientific and human resource assistance.

Ambio, 2004 Feb, 33(1-2), 13 - 23
Mitigation of environmental problems in Lake Victoria, East Africa: causal chain and policy options analyses; Odada EO et al.; Lake Victoria is an international waterbody that offers the riparian communities a large number of extremely important environmental services . Over the past three decades or so, the lake has come under increasing and considerable pressure from a variety of interlinked human activities such as overfishing, species introductions, industrial pollution, eutrophication, and sedimentation . In this paper we examine the root causes for overfishing and pollution in Lake Victoria and give possible policy options that can help remediate or mitigate the environmental degradation.

Chemosphere, 2004 Jun, 55(10), 1429 - 38
A new protocol to measure the effects of toxicants on daphnid-algae interactions; Clement B et al.; Inhibition of zooplankton grazing by toxicants present at sublethal concentrations in freshwater ecosystems can lead to uncontrolled algal growth and consequently exacerbate eutrophication problems . Short-term measurements of cladoceran grazing inhibition have been reported for some toxicants, but these studies do not mimic the actual interactions between microalgae, daphnids and toxicants, since algal growth is not allowed . On the opposite, algal blooms in complex microcosm or mesocosm assays have been interpreted as consequences on zooplankton, but effects on grazing, survival, growth or reproduction could not be easily discriminated . In this study, a simple assay with daphnids and microalgae is proposed to measure effects on grazing in dynamic conditions (algal growth over 6 days), and applied to copper and lindane . In the same time, direct effects on algal growth can be shown and taken into account . Results are compared with daphnid response measured with different endpoints (immobilization test and static grazing assay) . For both toxicants, effects at sublethal concentrations were demonstrated . Copper impaired daphnid grazing at 10 microg/l (60% inhibition) in the 48 h-static test and 15 microg/l (40% inhibition) in the 6 day-dynamic test, whereas 48 h-EC50 for daphnid mobility was 47 microg/l . The EC50s for lindane were 50 microg/l for daphnid grazing (48 h-static and 6 day-dynamic tests) and 383 microg/l for the immobilization test (48 h).

Sci Total Environ, 2004 May 5, 323(1-3), 211 - 8
Effects of nitrogen deposition on nitrogen cycling in an Aleppo pine stand in Athens, Greece; Michopoulos P et al.; High levels of nitrogen deposition measured in throughfall fluxes in 2002, reaching 38 kg ha(-1) year(-1), affected the biogeochemical cycle of N in an Aleppo pine (Pinus halepensis) stand situated in Athens, the capital of Greece . The N fluxes in bulk deposition were far lower than those in throughfall indicating high levels of dry deposition in the city of Athens . The amounts of N in litterfall and those stored in the forest floor and mineral soil were not high, while the mean residence time of N in the forest floor, derived from fluxes equations, decreased considerably due to the high levels of N fluxes in throughfall deposition . Nitrogen concentration in needle tissues was high and this resulted in a high ratio of N/Zn . Zinc availability was low due to the alkaline nature of soil in the study area . Fast N cycling may affect the living status of Aleppo pine, which is an oligotrophic plant species capable of occupying poor soil sites . Nitrogen eutrophication may adversely affect forests grown on calcareous soils by developing nutrition imbalances between N and micronutrients, the solubility of which depends on soil pH values.

J Environ Qual, 2004 Mar-Apr, 33(2), 678 - 84
Phosphorus leaching in relation to soil type and soil phosphorus content; Djodjic F et al.; Phosphorus losses from arable soils contribute to eutrophication of freshwater systems . In addition to losses through surface runoff, leaching has lately gained increased attention as an important P transport pathway . Increased P levels in arable soils have highlighted the necessity of establishing a relationship between actual P leaching and soil P levels . In this study, we measured leaching of total phosphorus (TP) and dissolved reactive phosphorus (DRP) during three years in undisturbed soil columns of five soils . The soils were collected at sites, established between 1957 and 1966, included in a long-term Swedish fertility experiment with four P fertilization levels at each site . Total P losses varied between 0.03 and 1.09 kg ha(-1) yr(-1), but no general correlation could be found between P concentrations and soil test P (Olsen P and phosphorus content in ammonium lactate extract {P-AL}) or P sorption indices (single-point phosphorus sorption index {PSI} and P sorption saturation) of the topsoil . Instead, water transport mechanism through the soil and subsoil properties seemed to be more important for P leaching than soil test P value in the topsoil . In one soil, where preferential flow was the dominant water transport pathway, water and P bypassed the high sorption capacity of the subsoil, resulting in high losses . On the other hand, P leaching from some soils was low in spite of high P applications due to high P sorption capacity in the subsoil . Therefore, site-specific factors may serve as indicators for P leaching losses, but a single, general indicator for all soil types was not found in this study.

J Environ Qual, 2004 Mar-Apr, 33(2), 576 - 80
Trophic transition in a lake on the Virginia coastal plain; Pensa MA et al.; To examine possible connections between lake trophic status and runoff from surrounding subwatersheds, we determined patterns of sediment and nutrient deposition in a hypereutrophic, 16-ha impoundment on the Virginia coastal plain . Spatial survey of nutrients in surface sediments documented a strong correlation between total P and extractable Fe (r2 = 0.53) . Elevated biogenic silica concentrations up to 0.25% by weight were measured in sections of the lake receiving perennial stream discharge . Sediment C to N ratios were > 20 in those same sections, suggesting a large allochthonous contribution to organic matter deposition . Sediment cores 0.9 to 2.3 m in length, representing 70 years of deposition, were analyzed to develop vertical profiles of changes in sediment and nutrient deposition in deltas downstream from two more-developed and three less-developed subwatersheds (with 49 and 9% commercial and residential development, respectively) . The average sediment weight percent +/- standard deviation of biogenic silica (0.027 +/- 0.037 vs . 0.009 +/- 0.006%) and total P (0.040 +/- 0.025 vs . 0.024 +/- 0.019%) was significantly higher downstream of more-developed subwatersheds . Using elevated P loadings and biogenic silica deposition as proxies for algal production, transition of the lake to its current hypereutrophic state appears to have occurred in the last 70 yr . Changes in trophic status as revealed by sediment analysis of this small lake on the Virginia coastal plain reflect a common pattern of eutrophication observed for the entire Chesapeake Bay drainage basin . Analysis of sediments from stream deltas appears to be a reasonable strategy for identifying and targeting subwatershed areas needing better management of nutrient runoff that otherwise would lead to eutrophication of downstream waters.

Water Sci Technol, 2004, 49(3), 101 - 8
Environmental effects of manure policy options in The Netherlands; Oenema O et al.; This study explores the effects of manure policy options for agricultural land in The Netherlands on nitrate leaching to groundwater, ammonia and nitrous oxide emissions to the atmosphere and on eutrophication of surface waters . The implementation of the farm gate balance MINAS at farm level, with levy-free N surpluses in the range of 300 to 40 kg per ha per year, and levy-free P surpluses in the range of 17.5 to 0.4 kg of P per ha per year, have been examined . Results indicate that nitrate concentrations in the upper groundwater are related to N surplus, land use, soil type and groundwater level . On dry sandy soils, the N surplus has to be below 60 to 140 kg of N per ha per year, depending on land use, to decrease the nitrate concentrations in the upper groundwater to below 50 mg nitrate per litre . Decreases of N and P concentrations in surface waters, upon lowering levy-free surpluses appear relatively small . For improving the ecological state of surface waters, we recommend a combination of low levy-free N and P surpluses with dredging P rich sediments, flushing of ditches, and decreasing discharges from other sources.

Water Sci Technol, 2004, 49(3), 37 - 45
Modelling diffuse nutrient flow in eutrophication control scenarios; Arheimer B et al.; The Swedish Water Management Research Programme (VASTRA) focuses on the development and demonstration of tools for more efficient eutrophication control when implementing the EU water framework directive in Sweden . During the first half of the programme, models for nitrogen flow were developed, and at present, similar models for phosphorus are under construction (e.g . HBV-P) . The programme is interdisciplinary, and scientists are collaborating in actor-games and focus group evaluations including scenario analysis . The scenarios modelled in VASTRA phase I, show that (i) changed agricultural practices can be the most effective and least expensive way to reduce nitrogen transport from land to the sea; (ii) constructed agricultural wetlands may only have small impact on riverine nitrogen transport in some regions, due to natural hydrometeorological dynamics; (iii) removing planktivorous fish may be an efficient way of reducing the algal concentrations in lakes without the undesired side-effect of increased nutrient load to the down-stream river system . In VASTRA phase II, one of the highlights will be interdisciplinary scenario-modelling of different measure strategies in a pilot catchment of southern Sweden (Ronne a).

Water Sci Technol, 2004, 49(3), 21 - 8
Modelling nutrient fluxes from diffuse and point emissions to river loads: the Estonian part of the transboundary Lake Peipsi/Chudskoe drainage basin (Russia/Estonia/Latvia); Mourad D et al.; First results are presented of a large-scale GIS-based nutrient transport modelling for the 1985-1999 period in the Estonian part of the transboundary drainage basin of Lake Peipsi (Estonian)/Chudskoe (Russian), one of the largest lakes in Europe, shared by Russia and Estonia . Although the lake is relatively undisturbed by human pollution, it is vulnerable for eutrophication by increased river loads, as shown in the past, when the north-eastern part of the former Soviet Union suffered from intensive agriculture . The collapse of the Soviet Union caused a dramatic decline in fertilizer application rates and widespread abandonment of agricultural land . Although concentration measurements and modelling results indicate a general decrease in nutrient loads, modelling is complicated by the transfer of nutrients from diffuse emissions, which is strongly governed by retention and assumed periodic release from storages within the river basin, like the root zone, tile drains, ditches, channels, bed sediments, floodplains and lakes . Modelling diffuse emission contribution to river loads can be improved by better knowledge about the spatial and temporal distribution of this retention and release within the drainage basin.

Environ Int, 2004 Jul, 30(5), 721 - 39
Life cycle assessment part 2: current impact assessment practice; Pennington DW et al.; Providing our society with goods and services contributes to a wide range of environmental impacts . Waste generation, emissions and the consumption of resources occur at many stages in a product's life cycle-from raw material extraction, energy acquisition, production and manufacturing, use, reuse, recycling, through to ultimate disposal . These all contribute to impacts such as climate change, stratospheric ozone depletion, photooxidant formation (smog), eutrophication, acidification, toxicological stress on human health and ecosystems, the depletion of resources and noise-among others . The need exists to address these product-related contributions more holistically and in an integrated manner, providing complimentary insights to those of regulatory/process-oriented methodologies . A previous article (Part 1, Rebitzer et al., 2004) outlined how to define and model a product's life cycle in current practice, as well as the methods and tools that are available for compiling the associated waste, emissions and resource consumption data into a life cycle inventory . This article highlights how practitioners and researchers from many domains have come together to provide indicators for the different impacts attributable to products in the life cycle impact assessment (LCIA) phase of life cycle assessment (LCA).

Environ Int, 2004 Jul, 30(5), 701 - 20
Life cycle assessment part 1: framework, goal and scope definition, inventory analysis, and applications; Rebitzer G et al.; Sustainable development requires methods and tools to measure and compare the environmental impacts of human activities for the provision of goods and services (both of which are summarized under the term "products") . Environmental impacts include those from emissions into the environment and through the consumption of resources, as well as other interventions (e.g., land use) associated with providing products that occur when extracting resources, producing materials, manufacturing the products, during consumption/use, and at the products' end-of-life (collection/sorting, reuse, recycling, waste disposal) . These emissions and consumptions contribute to a wide range of impacts, such as climate change, stratospheric ozone depletion, tropospheric ozone (smog) creation, eutrophication, acidification, toxicological stress on human health and ecosystems, the depletion of resources, water use, land use, and noise-among others . A clear need, therefore, exists to be proactive and to provide complimentary insights, apart from current regulatory practices, to help reduce such impacts . Practitioners and researchers from many domains come together in life cycle assessment (LCA) to calculate indicators of the aforementioned potential environmental impacts that are linked to products-supporting the identification of opportunities for pollution prevention and reductions in resource consumption while taking the entire product life cycle into consideration . This paper, part 1 in a series of two, introduces the LCA framework and procedure, outlines how to define and model a product's life cycle, and provides an overview of available methods and tools for tabulating and compiling associated emissions and resource consumption data in a life cycle inventory (LCI) . It also discusses the application of LCA in industry and policy making . The second paper, by Pennington et al . (Environ . Int . 2003, in press), highlights the key features, summarises available approaches, and outlines the key challenges of assessing the aforementioned inventory data in terms of contributions to environmental impacts (life cycle impact assessment, LCIA).

Ambio, 2003 Dec, 32(8), 577 - 85
Assessing Secchi and photic zone depth in the Baltic Sea from satellite data; Kratzer S et al.; Long-term trends in the Secchi depth of the Baltic Sea have been interpreted in terms of eutrophication . The spectral attenuation coefficient Kd (490) can be estimated from remote sensing data . Given the empirical and theoretical relationships between diffuse attenuation and Secchi depth, it is therefore possible to estimate the trophic state from remote sensing data . This paper considers relationships among remotely sensed and in-water measured K (490), and Secchi depth data obtained during dedicated sea-truthing campaigns in the eastern Baltic Proper in 1999 (4) and in the western Baltic Proper/Himmerfjarden area during 2001 and 2002 . In-water measurements are used to establish the relationship between the PAR and the spectral attenuation coefficient in the Baltic Sea via regression analysis . The analysis showed that in the area of investigation Kd(490) is about 1.48 times higher than Kd (PAR) . This relationship is then used to define the link between the photic zone depth and the remote sensing optical depth, Kd (490)-1 . The results show that the depth of the euphotic zone is about 6.8 times Kd (490)-1 . The regression analysis between Kd (PAR) and Secchi depth confirmed previous work that Kd (PAR) is about 1.7 of the inverse Secchi depth . Furthermore, an in-water algorithm between Secchi depth and Kd (490) is used to simulate a Secchi depth map of the Baltic Sea from SeaWiFS Kd(490) data . This map is verified against sea-truthing data . Kd (490) data derived from satellite is compared to in situ Kd (490), and the sources of error are discussed.

Environ Sci Technol, 2004 Mar 1, 38(5), 1487 - 95
Geochemical controls on the production and distribution of methylmercury in near-shore marine sediments; Hammerschmidt CR et al.; We examined temporal differences in sedimentary production of monomethylmercury (MMHg) at three sites in Long Island Sound (LIS) . Sediment-phase concentrations of Hg species decreased from west to east in LIS surface sediments, following the trend of organic matter . However, Hg methylation potentials, measured by incubation with an isotopic tracer (200Hg), increased from west to east . 200Hg methylation potentials were enhanced in August relative to March and June, attributable to differences in activity of sulfate-reducing bacteria . Organic matter and acid-volatile sulfide influenced the distribution coefficient (KD) of inorganic Hg (Hg(II) = total Hg - MMHg) and inhibited 200Hg methylation in surface sediments . 200Hg methylation varied inversely with the KD of Hg(II) and positively with the concentration of Hg(II), mostly as HgS0, in LIS pore waters . Accordingly, we posit that a principal control on MMHg production in low-sulfide, coastal marine sediments is partitioning of Hg(II) between particle and dissolved phases, which regulates availability of Hg substrate to methylating bacteria . Most of the partitioning in LIS sediments is due to Hg-organic associations . This suggests that reductions in the organic content of coastal sediment, a potential result of nutrient abatement programs intended to inhibit eutrophication of near-shore waters, could enhance MMHg production by increasing the bioavailability of the large reservoir of "legacy Hg" buried within the sediment.

Asia Pac J Clin Nutr . 2003;12 Suppl:S32.
Dietary phytase supplementation and the utilisation of phosphorus by Atlantic salmon (Salmo salar L.) fed a canola meal-based diet; Sajjadi M et al.; Background - Plant proteins offer a promising source of protein for fish meal replacement in aquafeeds, but there are some limitations to their use . Phytate is an antinutritional factor that found in many plant meal . Phytate phosphorus is lost via fish faeces, contributing to pollution and eutrophication of the aquatic environment . Phytase hydrolyses phytate to release phosphorus and it has been used successfully to increase phosphorus digestibility for several monogastric animals . Its potential with Atlantic salmon has yet to be tested thoroughly . Objective - To determine the effect of dietary phytase on phosphorus digestibility in Atlantic salmon fed a plant meal-based diet . Design - Four diets were made with canola meal as main protein source . The control diet contained 35% canola meal and three experimental diets were formulated to contain phytase; inorganic phosphorus (diabasic sodium phosphate); phytase and inorganic phosphorus . Outcomes - Phosphorus digestibility was significantly (P<0.05) higher in fish fed phytase supplemented diets in comparison with the control diet . The control fish had significantly lower bone ash (46.53 +/- 0.75%) and bone phosphorus (9.78 +/- 0.23%) content . Phosphorus load was the lowest in fish fed phytase supplemented diet (3.9g kg(-1)) and the highest value was observed in fish fed diet supplemented with inorganic phosphorus (8.1g kg(-1)) . Conclusions - Inclusion of phytase in an Atlantic salmon diet increased phytate phosphorus utilisation . The use of supplementary phytase was shown to be effective in Atlantic salmon feeds and to have the potential to limit pollution when plant proteins are used.

Environ Sci Pollut Res Int, 2004, 11(1), 11 - 7
Nutrient dynamics in shallow lakes of Northern Greece; Petaloti C et al.; GOAL, SCOPE, BACKGROUND: Shallow lakes display a number of features that set them apart from the more frequently studied deeper systems . The majority of lakes in Northern Greece are small to moderate in size with a relatively low depth and are considered as sites of high value of the wetland habitat . However, the water quality of these lakes has only been evaluated segmentally and occasionally . OBJECTIVE: The objectives of this study were to thoroughly investigate nitrogen and phosphorus speciation in lakes of a high ecological significance located in N . Greece, in order to evaluate their eutrophication status and possible nutrient limitation factors, and to investigate the main factors/sources that affect the water quality of these systems . METHODS: An extensive survey was carried out during the period from 1998-1999 . Water samples were collected on a monthly basis from lakes Koronia, Volvi, Doirani, Mikri Prespa and Megali Prespa located in N . Greece . Water quality parameters (temperature, dissolved oxygen, pH and conductivity), organic indices (COD, BOD5), and N- and P-species (NO3(-), NO2(-), NH4(+), and PO4(3-), Kieldahl nitrogen and acid-hydrolysable phosphorus) were determined according to standard methods for surface water . Statistical treatment of the data was employed . RESULTS AND CONCLUSIONS: The physicochemical parameters determined in the lakes studied revealed a high temporal variation . The trophic state of the lakes ranged from meso- to hypertrophic . The nutrient limiting factor varied among lakes suggesting either P-limitation conditions or mixed conditions changing from P- to N-limitation throughout the year . Urban/industrial activities and agricultural runoff are the major factors affecting all lakes, although with a varying contribution . RECOMMENDATION AND OUTLOOK: This lake-specific research offers valuable information about water quality and nutrient dynamics in lakes of significant ecological value located in N . Greece that can be useful for an effective pollution control/management of these systems . Due to the large intra-annual variability of certain physicochemical parameters, a properly designed monitoring program of lake water is recommended.

Ying Yong Sheng Tai Xue Bao, 2003 Nov, 14(11), 2057 - 61
{Advances in research of biological purification of eutrophic water body}; Quan W et al.; Eutrophication is a global problem, and the key of its controlling is to manipulate the structure of aquatic ecosystem, to recover the function of natural, healthy and stable aquatic ecosystem, and to improve the biological purification capability of eutrophic water body . Aquatic higher plant and vegetation is the most important primary producer in aquatic ecosystem, because of its large individual, long life cycle, and strong capability of absorbing nutrients . Maintaining and restoring a certain amount of aquatic plant could restrain the growth of phytoplankton, improve the biodiversity of aquatic ecosystem, and stabilize its structure . Aquatic animal plays an important role in material and energy cycles of aquatic ecosystem . Zooplankton and benthos can graze phytoplankton directly, so as to controll the number of phytoplankton . It is possible to improve the number of zooplankton by changing the structure of fish population, which might control the serious reproduction of phytoplankton, and achieve the goal of controlling eutrophication . The research of biological purification is still at its initial stage in China . In future, the following two aspects of researches should be enforced: the key technology of biological purification of aquatic higher plant and vegetation; the new model of breed aquatics . These technologies will have a important significance to controlling eutrophication and in sustainable utilization of water body.

Ying Yong Sheng Tai Xue Bao, 2003 Nov, 14(11), 1963 - 6
{Structural characteristics of phytoplankton community during harmful algae bloom in Jiaozhou Bay}; Liu D et al.; Based on two days survey in August, 2001 in Jiaozhou Bay, the structural characteristics of phytoplankton community during harmful algae bloom was studied . The results showed that phytoplankton community was composed mainly by the coastal warm species, which were dominated by the diatom including 37 species . Only 7 Pyrrorophya and 1 Chlorophyta species were identified . The highest value of species number appeared in the central of Jiaozhou Bay, which included 37 species, but the lowest value in the edge of Jiaozhou Bay was only 10 species . The highest value of cell abundance appeared in the eastern waters of Jiaozhou Bay, being 6.96 x 10(3) cell.m-3, and the lowest value appeared in the mouth of Jiaozhou Bay, being 3.18 x 10(6) cell.m-3 . The diversity and eveness of phytoplankton was the lowest in the eastern waters of Jiaozhou bay, but was higher in the mouth and the central of Jiaozhou Bay . Water mass movement and eutrophication were the main factors affecting the distribution of phytoplankton community in Jiaozhou Bay.

Bioresour Technol, 2004 May, 93(1), 71 - 5
Integrated vermi-pisciculture--an alternative option for recycling of solid municipal waste in rural India; Ghosh C; Vermicomposts as a biofertilizer can be a great option for pond manuring as they never cause any long term harm to the soil like chemical fertilizer . In this study vegetable and horticulture waste was used as an important media for vermiculture . Three separate cemented tanks (6 m(3) each) were used in the system as control tank, vermicompost fertilized tank and inorganic fertilizer manured tank . Monoculture of fish was carried out with cat fish, Clarias batrachus . The produced earthworms were used as fish feed . Regular monitoring of water parameter was conducted in three different ponds . Specifically, the algal biomass variation was quite helpful in analyzing the behavior of the ponds . NPK value of soil samples were analyzed intermittently to know the eutrophication level . Despite the hot summer temperature in northern part of India, which is not ideal for fish growth, we have recorded an encouraging growth performance in organic manured pond along with inorganic fertilizer treated and control pond . Among eutrophicated pond, the fish biomass from vermicompost fed pond showed an increasing trend compared to inorganic fertilizer treated pond . Water retention capacity of vermicompost pond soil was better in comparison to other ponds . Result shows that the low cost model by integrating two production system vermiculture and pisciculture could be a commercially and environmentally viable option.

Environ Toxicol Chem, 2004 Feb, 23(2), 521 - 9
A freshwater food web model for the combined effects of nutrients and insecticide stress and subsequent recovery; Traas TP et al.; A microcosm experiment that addressed the interaction between eutrophication processes and contaminants was analyzed using a food web model . Both direct and indirect effects of nutrient additions and a single insecticide application (chlorpyrifos) on biomass dynamics and recovery of functional groups were modeled . Direct toxicant effects on sensitive arthropods could be predicted reasonably well using concentration-response relationships from the laboratory with representative species . Model predictions showed that nutrient additions alone caused only small effects on toxicant fate and effects probably due to the relatively high dissipation rate of chlorpyrifos . Enhancement of eutrophication effects by the insecticide was relatively small and seemed to be additive . The recovery of some affected functional groups was hampered in the indoor microcosms due to their isolation from outdoor seed populations . Introducing recolonization scenarios in the model simulated dose-dependent recovery . Recolonization increased the recovering rate after exposure to the pesticide . Modeling can extend the use of microcosms as a link between laboratory and field as this allows the prediction of effects and recovery of ecosystems for concentrations that have not been experimentally tested.

J Environ Sci (China), 2003 Nov, 15(6), 728 - 33
Chemical forms and extractability of iron in sediments of three contrasting lakes of China and UK; Zhou QX et al.; Iron is a limiting factor for the eutrophication of lakes, especially those lakes that are enriched with phosphorus . Extractability of iron in sediments of West Lake and Taihu Lake in China and Lower Lough Erne in Northern Ireland of UK was comparatively investigated on the basis of analysing chemical forms of iron using different extractants . It was shown that extractable iron in sediments of the lakes was greatly different using various extractants . Reactive iron or easily released iron such as "active" iron oxides, total free iron oxide and water-soluble iron was not high, only accounting for 0.01%-0.15% of total iron . The efficiency of the extractants for exchangeable iron was decreased in the sequence 0.1 mol/L HCl >> DTPA + TEA mixed solution > 1 mol/L NH4OAc > 0.5 mol/L MgCl2 = 0.5 mol/L CaCl2 . It seems that the complexion of iron by organic matter was not strong because the concentration of organically bound iron was significantly lower than the concentration it was forecasted . Extractable iron is not entirely consistent with or dependent on total iron in lake sediments . To a certain extent, phosphate can inhibit the release of iron in sediments of the lakes . The selection of extractants is thus the first key step to evaluate bioavailability of iron in lake sediments.

J Gen Appl Microbiol, 2003 Dec, 49(6), 329 - 36
Amino acids as main substrates for sulfate-reducing bacteria in surface sediment of a eutrophic bay; Takii S; The inner part of Tokyo Bay, Japan, is highly eutrophicated as shown by the frequent occurrence of red tide . The bottom water is anoxic during warm seasons especially at artificially dredged sites . In the sediment slurries prepared from surface sediment samples collected from the dredged sites, substrate addition stimulated the consumption of sulfate during anaerobic incubation . Of the substrates added, the seston composed mainly of diatom stimulated consumption more than lactate and acetate . Its effect was nearly equal to that of casamino acids . Casamino acids and some amino acids also accelerated the rate of sulfate reduction measured by the tracer method in sediment samples more than lactate or acetate . Anaerobic incubation of the sediment slurry amended with casamino acids showed that the consumption of amino acids was retarded by the addition of molybdate (final concentration; 20 mM) . In the slurry amended with only molybdate, glutamate was accumulated distinctively and linearly with time . Its accumulation rate in molar base was comparable to the rate of sulfate reduction . These results suggested that amino acids were the main substrates for sulfate-reducing bacteria (SRB) in the sediment . The MPN values of SRB in these sediment samples were often higher with the enumeration medium containing casamino acids instead of lactate . Furthermore, during a week incubation of sediment slurries amended with substrates, casamino acids and seston more greatly stimulated the growth of SRB enumerated by both media than lactate.

Water Res, 2004 Feb, 38(3), 507 - 16
Phosphorus in periphyton mats provides the best metric for detecting low-level P enrichment in an oligotrophic wetland; Gaiser EE et al.; Growing concern over the ecological consequence of phosphorus (P) enrichment in freshwater wetlands has elicited considerable debate over the concentration of water column P associated with eutrophication . In the oligotrophic Everglades, the displacement of native communities by enriched ones is widespread and has occurred at sites experiencing only minimal elevations in P input . To help define regulatory criteria for P inputs to the Everglades, we constructed an experiment that mimics P input to the natural system by continuously delivering P at concentrations elevated 5, 15 and 30 microgl(-1) above ambient to 100-m long flow-through channels . We compared patterns of P accumulation in the water, periphyton, detritus and soils among the channel treatments and also along a 16 km transect from an enriched canal that inflows to the interior of the same marsh . Water column TP and SRP were unrelated to input TP concentration in both the experiment and the marsh transect . However, concentrations of TP in periphyton mats were significantly elevated at all levels of experimental enrichment and as far as 2 km downstream from water inputs into the marsh . Elevated periphyton TP was associated with significant loss of periphyton biomass . In oligotrophic wetlands, traditional measures of water column SRP and TP will substantially underestimate P loading because biotically incorporated P is displaced from the water column to benthic surfaces . Using periphyton TP as a metric of P enrichment is uncomplicated and analogous to pelagic TP assessments in lakes where most P is sequestered in phytoplankton.

Mikrobiol Z, 2003 Sep-Oct, 65(5), 3 - 7
{Variation of bacterioplankton number in the north-western part of the Black Sea depending on hydrological and hydrochemical factors}; Kovaleva NV; Quantitative analysis of total bacteria numbers variations under influence of river outflow and development of anaerobic conditions has been carried out on the basis of long-term field research in the north-western part of the Black Sea . The regressive equations describing dependence of the total bacteria number on temperature, salinity and water saturation with oxygen have been calculated . These results allow to characterize more completely the regularities of eutrophication processes on the Black Sea shelf.

J Environ Manage, 2003 Dec, 69(4), 323 - 37
The setting of standards for agricultural nitrogen emissions: a case study of the Delphi technique; Angus AJ et al.; The Delphi technique is a means of aggregating the judgement of a panel of experts in order to improve the quality of decision-making . This paper provides a case study of the technique by undertaking a three-round Delphi study to determine a package of best available techniques to reduce nitrogen emissions from a poultry unit under the Integrated Pollution Prevention and Control Directive (IPPC) . Forms of nitrogen addressed included ammonia (NH3), nitrous oxide (N2O) nitrogen oxides (NOx), dusts and nitrate (NO3-), with the study providing a means to prioritise the pollution concerns on different spatial scales . The priority pollutant issues were the contribution of NH3 to eutrophication, the global cooling effect of NH4+ aerosol, the role of NH4+ as a vector for atmospheric transport of NOx and SO2, the contribution of N2O to global warming, and NO3- leaching . Reduced nitrogen (NHx) was rated as a priority on all scales, while N2O and NO3- were rated as priorities only on global and local scales, respectively . The study indicated the need for abatement techniques at each stage of poultry rearing and waste management, with particular attention to reduce NH3 emissions, reflecting the priority pollutant concerns . Measures identified by the panel include maintenance of dry litter, low emission removal of litter from housing and storage of litter under cover . Once the litter has left the farm, this should either be used as a biofuel for electricity generation or rapidly incorporated into agricultural soils . The amounts and timing of manure application should be tuned to crop needs . Uncertainties in the Delphi technique limit its suitability as a stand-alone decision making tool . However, the Delphi technique proved useful in identifying priority pollutant issues, areas of agreement, disagreement and where information is lacking . This demonstrates its use when dealing with the complex issues of prioritising pollution issues and abatement approaches.

J Environ Qual, 2003 Nov-Dec, 32(6), 2334 - 40
Halting the upward trend in soluble phosphorus transported from a grassland catchment; Smith RV et al.; An upward trend in soluble reactive phosphorus (SRP) concentrations in Northern Ireland rivers leading to increased eutrophication has been reported for the last two decades . To identify if a similar trend could be observed in land drainage waters SRP and other P fractions were measured weekly from 1989 to 1997 in land drainage from a 9-ha grassland catchment in Northern Ireland that had a mean P surplus applied of 23.4 kg P ha(-1) yr(-1) . Regressions of annual median concentrations of P fractions in land drainage waters against time for 1989 through to 1997 showed significant increases of SRP and soluble unreactive phosphorus (SUP) of 2.4 and 1.2 microg P L(-1) yr(-1), respectively . However, the annual flow-weighted concentrations and loads of all P fractions did not show significant increases with time . During the period 1998-2000 a change of management was introduced when only maintenance dressings of P were applied to the catchment according to Ministry of Agriculture, Fisheries and Food guidelines . This resulted in significant reductions in SRP concentrations in 2000 compared with 1997.

J Environ Qual, 2003 Nov-Dec, 32(6), 2007 - 16
Contribution of particulate phosphorus to runoff phosphorus bioavailability; Uusitalo R et al.; Runoff P associated with eroded soil is partly solubilized in receiving waters and contributes to eutrophication, but the significance of particulate phosphorus (PP) in the eutrophying P load is debatable . We assessed losses of bioavailable P fractions in field runoff from fine-textured soils (Cryaquepts) . Surface runoff at four sites and drain-flow at two of them was sampled . In addition to dissolved molybdate-reactive phosphorus (DRP) losses, two estimates of bioavailable PP losses were made: (i) desorbable PP, assessed by anion exchange resin-extraction (AER-PP) and (ii) redox-sensitive PP, assessed by extraction with bicarbonate and dithionite (BD-PP) . Annual losses of BD-PP and AER-PP were derived from the relationships (R2 = 0.77-0.96) between PP and these P forms . Losses of BD-PP in surface runoff (94-1340 g ha(-1)) were typically threefold to fivefold those of DRP (29-510 kg ha(-1)) or AER-PP (13-270 g ha(-1)) . Where monitored, drainflow P losses were substantial, at one of the sites even far greater than those via the surface pathway . Typical runoff DRP concentration at the site with the highest Olsen-P status (69-82 mg kg(-1)) was about 10-fold that at the site with the lowest Olsen P (31-45 mg kg(-1)), whereas the difference in AER-PP per mass unit of sediment was only threefold, and that of BD-PP 2.5-fold . Bioavailable P losses were greatly influenced by PP runoff, especially so on soils with a moderate P status that produced runoff with a relatively low DRP concentration.

Ying Yong Sheng Tai Xue Bao, 2003 Aug, 14(8), 1351 - 3
{Effects of rehabilitation of submerged macrophytes on nutrient level of a eutrophic lake}; Wu Z et al.; The effects of rehabilitation of submerged aquatic vegetation on nutrient level of eutrophic waters were investigated by using large-scale enclosure system installed in a hyper-eutrophicated lake, Lake Donghu of Wuhan . The concentrations of total nitrogen (TN) and total phosphorus (TP) of the enclosures with artificially recovered submerged macrophytes were significantly lower than those of the macrophyte-free control enclosure and the lake water, and the TP of macrophyte enclosure was found to be around 0.1 mg.L-1 and relatively stable . The concentration of ammonia and nitrite of the macrophyte enclosures were lower than those of the control and the lake water . However, the nitrate concentrations did not differ among the various water bodies . It was demonstrated that re-establishment of submerged macrophytes could efficiently reduce the nutrient level and thus control the overgrowth of the undesirable algae and improve water quality in the eutrophic lakes.

Water Sci Technol, 2003, 48(7), 89 - 96
Hydrotechnical facilities within the Chernobyl nuclear power plant exclusion zone: impacts on hydrologic regime and plant growth patterns of floodplain water bodies of the Pripyat River; Gudkov DI et al.; As result of the Chernobyl nuclear power plant accident the territory of the left-bank flood-lands of the Pripyat River have undergone intensive radionuclide contamination . With the purpose of preventing the washing away of radioactive substances, a complex of flood protection dams was constructed . This construction changed the hydrological regime of these territories and caused overgrowth by higher aquatic plants . Absence of a flowing mode of reservoirs, the stagnant phenomena during spring and seasonal high waters on the embank site have caused amplification of eutrophication processes, swamping and, connected with it, increase of water-marsh floristic complex in the structure of the vegetative cover.

Ecotoxicology, 2003 Oct, 12(5), 405 - 16
The biology of Oreochromis niloticus in a polluted canal; Khallaf EA et al.; In the present investigation, length-weight relationship, condition factor, age, growth, mortality, gonadosomatic index (GSI) and fecundity of tilapias (Bolti in Arabic): Oreochromis niloticus, from Shanawan drainage canal (SDC), Al-Minufiya Province, Egypt, were studied . This was carried out on 162 fish samples collected during the period from April 1992 to May 1993 . Oreochromis niloticus was found to attain sexual maturity early (8-9 cm), was more fecund (1,234-3,893) and has high mortality rates (91% for males and 94% for females) . A comparison of the various parameters of O . niloticus from SDC with those of other authors in different localities and times in Egypt revealed year-to-year and geographically significant differences in relation to variation in weight with length, condition factor, fecundity, growth and mortality rates . These differences were discussed and were found to be attributed to the effect of eutrophication and pollution on the growth, age and other biological aspects of O . niloticius . Multiple regression analysis showed that only female GSI correlated significantly with pesticides and heavy metals contamination.

Environ Pollut, 2004, 127(3), 377 - 84
Use of cyanobacteria to assess water quality in running waters; Douterelo I et al.; Epilithic cyanobacterial communities in rivers in the province of Madrid (Spain) and their relationship with water quality were studied . Sampling locations above and below outlets for sewage effluent and other wastes from human settlements were selected . We aimed to evaluate the use of cyanobacteria as potential indicators of pollution in running waters . Large increases in nutrient concentrations were always observed at downstream sampling sites . A decrease in species richness and the Margalef diversity index were associated with these increases in nutrient load . Differences in cyanobacterial community structure were also observed . A higher proportion of cyanobacteria belonging to the Oscillatoriales order predominated at sampling sites with higher nutrient content . However, Nostocales species were more abundant at upstream sites characterized by lower nutrient load than at downstream locations . The soluble reactive phosphate (SRP) had a threshold effect on cyanobacterial biomass: a decrease in phycobiliprotein content as SRP increased, reaching a minimum, followed by an increase in abundance . This increase may be attributed to hypertrophic conditions in those locations . Our results and literature data confirm the suitability of this phototroph community for monitoring eutrophication in rivers

Water Sci Technol, 2003, 48(5), 215 - 22
Treatment of freshwater fish farm effluent using constructed wetlands: the role of plants and substrate; Naylor S et al.; Freshwater fish farm effluents have low nutrient concentrations but high flow rates, resulting in pollutant load, especially phosphorus (P), causing eutrophication . The feasibility was tested of a treatment combining, within a single constructed wetland, the contribution of macrophytes for reducing organic matter and nitrogen (N), with the high efficiency of steel slag and limestone for P removal . Twenty subsurface flow (SSF) basins of 280 L with different combinations of plants (Phragmites communis or Typha latifolia) and substrates (steel slag, limestone, gravel, peat) were fed with a reconstituted fish farm effluent in a greenhouse experiment . Pollutant removal was generally very good under all treatments . N and organic matter removal were correlated with plant biomass while P removal was better in substrates with steel slag and limestone . However, the high pH of the P-adsorbing substrate was detrimental to plant growth so that no combination of plants and substrates could maximise in one step the simultaneous removal of all evaluated pollutants . Therefore, the use of two sequential units is recommended, a first one consisting of a macrophyte planted basin using a neutral substrate to remove organic matter and N, followed by a second unplanted basin containing only a P-adsorbing substrate.

Mar Pollut Bull, 2003 Nov, 46(11), 1495 - 503
Effects of organic pollution on the initial development of fouling communities in a tropical bay, Brazil; Mayer-Pinto M et al.; Transplantation of artificial panels between a polluted and an unpolluted site was used to evaluate eutrophication effects on the development of fouling communities in Ilha Grande Bay, SE Brazil . Organic pollution changed the relative dominance of species in the fouling communities of transplanted panels, although, their richness, evenness, and specific composition did not change . The chlorophyte Ulva sp . occurred only in the polluted site and in panels transplanted to it, whereas the bryozoan Aetea lingulata was found only in the unpolluted site and in panels transplanted to this site . These species are therefore good pollution indicators . The best pollution indicators, however, were amphipods and Spionidae polychaetes which formed mucous tubes . These groups had significantly higher values of percent cover (p<0.0001) in the polluted site and in panels transferred to it . The dominance shift is the first evidence that more meaningful changes can occur in the structure of fouling communities on a long-term scale.

Mar Pollut Bull, 2003 Nov, 46(11), 1434 - 49
Changes in the seasonal cycles of inorganic nutrients in the coastal zone of the southeastern North Sea from 1960 to 1997: effects of eutrophication and sensitivity to meteoclimatic factors; Fock HO; A long-term analysis of seasonal cycles of inorganic nutrients by means of a seasonal index is presented for the German Bight and the southern Wadden Sea (SE North Sea) . Multivariate analysis for the German Bight data series revealed dependence of ammonium and phosphate index time series on dissolved inorganic nitrogen concentrations and riverine nutrient loads . Both indices are assumed to reflect seasonal dynamics of remineralisation processes associated with increased supply of organic matter . Temporal analysis revealed breaks in nutrient dynamics in 1970/1972 and 1979/1980 . After 1970/1972, an unprecedented increase in the summer concentrations of mineralisation endproducts with correspondingly low index values were observed, which further declined after 1979/1980 . Further breaks for Wadden Sea data series were identified in 1985 and 1988/1989 . The indicative value of the temporal breaks with respect to eutrophication is discussed against the background of changes in meteoclimatic factors and local environmental conditions . Collated information on eutrophication effects was consistent with the observed breaks . It is suggested that the break in 1970/1972 in the German Bight was the first sign of ecosystem response to eutrophication in the SE North Sea.

Environ Toxicol Chem, 2003 Nov, 22(11), 2789 - 99
Polychlorinated biphenyls and organochlorine pesticides in Baltic and Atlantic gray seal (Halichoerus grypus) pups; Sormo EG et al.; Organochlorine pollutants (OCs), such as polychlorinated biphenyls (PCBs), DDT, chlordanes (CHLs), hexachlorobenzene (HCB) and hexachlorocyclohexanes (HCHs) were determined in blubber biopsies from free-ranging Baltic and Atlantic gray seal (Halichoerus grypus) pups . Well-fed pups from the Baltic Sea had concentrations of DDT, PCBs, and HCHs that were 2 to 10 times higher than in corresponding pups from populations in the Atlantic Ocean . The OC pattern in the Baltic seals differed significantly from that of their Atlantic relatives, reflecting the predominance of regional point source inputs into the Baltic Sea and long-range atmospheric inputs into the Atlantic Ocean . The differences in the pattern of the compounds also indicated an enhanced metabolism of the more metabolizable compounds in the more contaminated Baltic seals . Surprisingly, the proportions of the high chlorinated and low-volatile PCB congeners (> 6 Cl atoms) were comparable or lower in the Baltic pups as compared to the Atlantic pups . This difference might be due to Baltic seals occupying a lower trophic level than Atlantic seals and/or to the eutrophication situation in the Baltic Sea, which causes sedimentation of these PCB congeners . Significantly higher OC concentrations were found in starved and/or abandoned Baltic pups as compared to well-fed pups . The most contaminated Baltic seal pups in the present study had PCB concentrations that are comparable or higher than those reported to impair the immune systems and vitamin A dynamics in phocids.

Ying Yong Sheng Tai Xue Bao, 2003 Jul, 14(7), 1140 - 2
{Response of Prorocentrum minimum growth to zinc limitation}; Hu H et al.; Studies on the growth and physiological response of red tide alga Prorocentrum minimum to three Zn2+ levels were showed that the specific growth rate and biomass were limited in low Zn(2+)-grown cells (1.4 pmol.L-1, which were 0.40 d-1 and 51,100 cell.ml-1 respectively . The specific growth rate was not significantly different when the Zn2+ concentration in medium was increased over 24.4 pmol.L-1, but there was a slight decrease in biomass; however, both specific growth rate and biomass were much higher than those in low Zn(2+)-grown cells . It was also showed that chlorophyll a synthesis was limited due to Zn2+ deficient, and therefore, the cells became light saturated at higher irradiance under Zn-limited condition . Light-saturated photosynthetic rates (Pm) and photosynthetic efficiency (alpha) increased significantly with increasing Zn2+ concentrations . It was concluded that Zn2+ concentration might be one of the key factors affecting red tide blooms in eutrophication environment.

Ying Yong Sheng Tai Xue Bao, 2003 Jul, 14(7), 1117 - 21
{Effects of terrestrial input on the harmful algal bloom area--with aluminum as an example}; Ren J et al.; In recent years, eutrophication and frequently occurred harmful algal blooms (HAB) become serious in the coastal area near Changjiang River estuary, and the nutrients came from Changjiang River may be the main sources for them . Aluminum could be used as a useful tracer for the terrestrial input and the movement of different water mass, since it enters into the natural water with the erosion products of soil and rock, and its residence time in the ocean is short and uneasy to be disturbed by the activities of human being . Based on our results, the concentration of dissolved Al was higher in Autumn than in Summer, and showed some relationships with the salinity and suspended particulate matter (SPM) . The concentration of Al in the HAB area was higher than 0.04 mumol.L-1, which showed the significant influence from the terrestrial input . The concentration of dissolved Al decreased nearly 40% after the occurrence of HAB, and the flocculation of dissolved Al and its absorption onto the surfaces of biogenic particles might be the main reasons . There still need further study about the variation of Al forms and its mechanism during the occurrence of HAB.

Ying Yong Sheng Tai Xue Bao, 2003 Jul, 14(7), 1097 - 101
{Nutrient distribution and its relationship with occurrence of red tide in coastal area of East China Sea}; Han X et al.; Nutrient (NO3(-)-N, PO4(3-)-P, Sio3(2-)-Si, NH4(+)-N, etc.) concentrations in coastal area of East China Sea were measured during April 25 to May 2, 2002, and the relationship between the spatial distribution of the nutrients and the red tide occurrence in the studied area was analyzed . The results showed that compared to the 1st class seawater quality of the national standard, the concentrations of dissolved inorganic nitrogen (DIN) and PO4(-)-P were 46% and 60% higher, respectively, showing that the studied area, especially the Changjiang River estuary and the Hangzhou Bay, was at a disadvantage of eutrophication . Furthermore, the nutrient concentrations inshore were much higher than those offshore, and the isolines nearly paralleled with the coastline, meaning that the nutrient distributions were mainly influenced by terrestrial discharges . It also showed that the relatively high concentrations of nutrients, especially DIN and PO4(3-)-P, might result in the red-tide occurrence . However, the red tide did not occur in the area with the highest concentrations of the nutrients, further demonstrating that the eutrophication was not the unique environmental factor inducing red-tide occurrence.

Ying Yong Sheng Tai Xue Bao, 2003 Jul, 14(7), 1093 - 6
{Distributions of COD and petroleum hydrocarbons and their relationships with occurrence of red tide in East China Sea}; Zhang C et al.; Based on the data of COD and petroleum hydrocarbons collected in the cruise from April 25 to May 2, 2002 in intensive red tide occurrence areas in East China Sea, the distribution of COD, and petroleum hydrocarbons and the eutrophication index(EI) were analyzed . The results showed that the EI and COD value were both high in coastal water, and decreased gradually away from shore . After the preliminary study on the relationships between correlative factors and occurrence of red tide, it was found that high EI and COD were necessary . There would be great chances for the red tide to break out under conditions that the EI was between 2.5 and 15 and COD concentration was between 0.8 to 1.4 mg.L-1 in seawater, along with the favorable temperature and salinity.

Ying Yong Sheng Tai Xue Bao, 2003 Jul, 14(7), 1065 - 9
{Ecological characteristics of Prorocentrum dentatum and the cause of harmful algal bloom formation in China Sea}; Wang J et al.; Large-scale harmful alga bloom (HAB) has been found in Changjiang River estuary and Zhoushan archipelago in recent three years, and the alga is Prorocentrum dentatum, which distributes in the sea areas with high salinity and (may) originates in outer sea area . Data from recent HAB rapid monitoring and ecological investigation were analyzed to study its ecological characteristics and forming inducement . The results showed that the most suitable temperature and salinity range for HAB forming was from 18 degrees C to 22 degrees C and from 21 to 31, respectively . The P . dentatum was motile and owned diurnal vertical migration bringing them the advantages in obtaining light and nutrients . Eutrophication was the preliminary condition, and water temperature, nitrate content, upwelling current, and strong competence on low phosphate environment were important to cause and maintain HAB.

Mar Pollut Bull, 2003 Oct, 46(10), 1224 - 44
Ecological condition of US Mid-Atlantic estuaries, 1997-1998; Kiddon JA et al.; The Mid-Atlantic Integrated Assessment (MAIA-Estuaries) evaluated ecological conditions in US Mid-Atlantic estuaries during the summers of 1997 and 1998 . Over 800 probability-based stations were monitored in four main estuarine systems--Chesapeake Bay, the Delaware Estuary, Maryland and Virginian coastal bays, and the Albemarle-Pamlico Estuarine System . Twelve smaller estuaries within the four main systems were also assessed to establish variance at the local scale . A subset of the MAIA-Estuaries data is used here to estimate the extent of eutrophication, sediment contamination, and benthic degradation in mid-Atlantic estuaries . An Environmental Report Card and Index of Environmental Integrity summarize conditions in individual estuaries, the four estuarine systems, and the entire MAIA region . Roughly 20-50% of the region showed signs of eutrophication (high nutrients, excessive production of organic matter, poor water clarity, or depleted dissolved oxygen), 30% had contaminated sediments, and 37% had degraded benthic communities . Compared with the Environmental Monitoring and Assessment Program (EMAP)-Virginian Province study in 1990-1993, larger fractions of Chesapeake Bay (17%) and Delaware River (32%) had increased metals or organics in sediments.

Curr Opin Infect Dis, 2003 Oct, 16(5), 461 - 5
Food poisoning associated with biotoxins in fish and shellfish; Brett MM; PURPOSE OF REVIEW: In recent times the number of blooms of algae that produce toxins has increased in frequency, intensity and geographical distribution . This review describes some of the illnesses caused by fish and shellfish contaminated with toxins produced by marine algae and by bacteria . RECENT FINDINGS: The increase in toxic algal blooms may be a result of increased awareness, aquaculture, eutrophication, or transport of cysts in ship ballast . Improved chemical methods for the detection of algal toxins are now being developed, and so the number of toxins recognized is increasing . Toxicological data on some of these algal toxins are lacking . Despite the increase in occurrence of algal toxins, scombrotoxic poisoning remains the most common cause of food poisoning associated with the consumption of fish and shellfish . This may be real or it may be a reflection of lack of suitable tests for algal toxins or under-recognition by workers in health care . SUMMARY: The major problem worldwide in this field is the lack of pure toxins for use in developing and standardizing chemical methods for toxin detection . Such methods would permit increased testing of both food and clinical specimens, and hence would prevent the entry of toxic food into the food chain and increase laboratory confirmation of incidents of illness.

Chemosphere, 2003 Nov, 53(7), 773 - 8
Influence of eutrophication on the coagulation efficiency in reservoir water; Cheng WP et al.; Water from the three reservoirs, Min-ter, Li-yu-ten and Yun-ho-shen, was examined for concentration of chlorophyll a, ultraviolet absorption (UV(254)), fluorescence intensity (FI), concentration of dissolved organic carbon (DOC), and fractionation of dissolved molecules by molecular weight . The water samples were collected over the change from spring to summer (May to July but before the typhoon season) when the water temperature and extent of eutrophication increase . Analytical results indicate that the concentration of DOC is proportional to the concentration of chlorophyll a, but not to the values of UV(254) and FI . Therefore, eutrophication, extraneous contaminants of small molecules, and the extracellular products of algae cause an increase in DOC, but a decrease in the proportion of large organic molecules such as of humic substances . The fraction of DOC with a molecular weight of less than 5000 Da increases with the concentration of chlorophyll a . All these data suggest that changes in the quality of water after eutrophication make the treatment of drinking water more difficult . The method of enhanced coagulation was recently developed for removing DOC . However, the results of this paper demonstrate that the efficiency of DOC removal falls as the degree of eutrophication increases . When the percentage of DOC with small molecules excreted by algae increased by 1%, the efficiency of DOC removal decreased by approximately 1%, implying that enhanced coagulation are not able to remove the DOC excreted by the algae during eutrophication, and resulting an increased concentration of trihalomethanes formation in water disinfections process.

J Environ Biol, 2003 Jan, 24(1), 55 - 61
Complex dynamics of toxin producing algal species and primary productivity in two water ponds of Faizabad; Dwivedi BK et al.; In order to develop a method of predicting and assessing pond eutrophication, which is a serious environmental problem, and to propose effective measure of improvement of water quality . The present study was performed to measure water quality variables, primary productivity, chl-a and biomass of toxin producing algal species and fish production . High nutrient influx and toxin producing algal species have been observed during June 1999 to May 2000 in two water bodies {Girija Kund (A) and Maqubara pond (B)} of Faizabad . The maximum chl-a concentration, toxins producing algal species biomass were found to be 415.00 and 515.00 in pond A, while 451.00 microg/l and 541.22 mg/l in pond B, respectively in the case of Microcystis aeruginosa . Ecological parameters to evaluate GPP, NPP and CR were found to be 297.00, 134.000 and 182.00 mgCm3/h in summer season in pond B, respectively which is higher than pond A . A poor association existed between chl-a and GPP . Temporal variation (Photosynthetic rate) in A(max) & P(max) was also observed to evaluate the productivity of pond . Annual fish production potential of the ponds A and B has been estimated to be around 342.00 Kg and 204 . 00 Kg, respectively which may be due to the presence of toxin producing algal species.

J Environ Biol, 2003 Jan, 24(1), 29 - 38
Dynamics of nitrogen, phosphorus, algal biomass, and suspended solids in an artificial lentic ecosystem and significant implications of regional hydrology on trophic status; An KG et al.; Chemical and biological parameters were analyzed to examine how regional hydrological fluctuations influence water quality of a artificial lentic ecosystem over a two-year period The intensity of seasonal monsoon rain accounted for most of annual inflow and discharge and influenced flow pathway (interflow vs . overflow), resulting in a modification of chemical and biological conditions . Sharp contrasting interannual hydrology of intense vs . weak monsoon occurred during the study . The intense monsoon disrupted thermal stratification and resulted in ionic dilution, high TP and high inorganic solids (NVSS) in the headwater reach . The variation of NVSS accounted 75% of TP variation (slope = 4.14, p < 0.01, n = 48) . Regression analysis of residual chlorophyll-a (Chl) versus flushing rate indicated that short hydraulic retention time and high mineral turbidity affected algal growth in the headwater reach during summer monsoon . In contrast, severe drought during weak monsoon produced strong thermal stratification, low inorganic solids, high total dissolved solids (TDS), and low TP in the entire system . In addition, Chl concentrations were controlled by phosphorus . Based on the physical, chemical and biological parameters, riverine conditions, dominated during the intense monsoon, but lacustrine conditions were evident during the weak monsoon . The interannual dynamics suggest that monsoon seasonality is considered the main forcing factor regulating overall functions and processes of the waterbody and this characteristic has an important implication to eutrophication of the system.

Ambio, 2003 Jun, 32(4), 287 - 94
Assessing reference conditions according to the European Water Framework Directive using modelling and analysis of historical data: an example from Randers Fjord, Denmark; Nielsen K et al.; The European Water Framework Directive (WFD) requires the definition of reference conditions, i.e . pristine conditions, for all surface waters . As the present state of Danish coastal waters cannot be referred to as pristine, reference conditions have to be assessed by analysis of historical data or by the use of models . Using Randers Fjord as an example, the aim of this work was i) to demonstrate possibilities and restrictions of assessing reference conditions by historical data and by modelling; and ii) to demonstrate how ecological conditions have changed along with eutrophication . The ample historical data from Randers Fjord allowed us to assess reference conditions with respect to benthic macrophytes and benthic fauna . Models of varying complexity enabled us to assess reference conditions for nutrients, chlorophyll a, Secchi depth, and eelgrass . We conclude that models can be a useful supplement to assess reference conditions, though they are presently restricted by the lack of quantitative links between eutrophication and species composition.

Evol Dev, 2003 Sep-Oct, 5(5), 494 - 507
Phyletic patterns of early development in gastropod molluscs; Lindberg DR et al.; Cell lineage data for 30 exemplar gastropod taxa representing all major subclades and the outgroup Polyplacophora were examined for phylogenetic signal using cladistic analysis . Most cell lineages show phyletic trends of acceleration or retardation relative to the outgroup and more basal ingroup taxa, and when coded this variation is phylo-genetically informative . PAUP analyses of a cell lineage data set under three sets of character ordering assumptions produced similar tree topologies . The topologies of the strict consensus trees for both ordered and Dollo (near irreversibility of character transformations) character assumptions were similar, whereas the unordered character assumption recovers the least phyletic information . The cell lineage cladograms are also in agreement with the fossil record of the timing and sequence of gastropod subclade origination . A long branch lies between the Patellogastropoda+Vetigastropoda grade and the Neritopsina+Apogastropoda clade . The geological timing of this long branch is correlated with the first large-scale terrestrially derived eutrophication of the near-shore marine habitat, and one possible explanation for this branch may be a developmental shift associated with the evolution of feeding larvae in response to the more productive conditions in the near-shore water column . Although character transformations are highly ordered in this data set, developmental rate characters (like all other morphological and molecular characters) are also subject to homoplasy . Finally, this study further supports the hypothesis that early development of gastropod molluscs has conserved a strong phyletic signal for about half a billion years.

Mar Pollut Bull, 2003 Sep, 46(9), 1174 - 8
Eutrophication risk assessment in coastal embayments using simple statistical models; Arhonditsis G et al.; A statistical methodology is proposed for assessing the risk of eutrophication in marine coastal embayments . The procedure followed was the development of regression models relating the levels of chlorophyll a (Chl) with the concentration of the limiting nutrient--usually nitrogen--and the renewal rate of the systems . The method was applied in the Gulf of Gera, Island of Lesvos, Aegean Sea and a surrogate for renewal rate was created using the Canberra metric as a measure of the resemblance between the Gulf and the oligotrophic waters of the open sea in terms of their physical, chemical and biological properties . The Chl-total dissolved nitrogen-renewal rate regression model was the most significant, accounting for 60% of the variation observed in Chl . Predicted distributions of Chl for various combinations of the independent variables, based on Bayesian analysis of the models, enabled comparison of the outcomes of specific scenarios of interest as well as further analysis of the system dynamics . The present statistical approach can be used as a methodological tool for testing the resilience of coastal ecosystems under alternative managerial schemes and levels of exogenous nutrient loading.

Ying Yong Sheng Tai Xue Bao, 2003 May, 14(5), 747 - 52
{Diversity patterns in intertidal communities of three southern islands of Changshan archipelago}; Zhuang S et al.; The diversity pattern of intertidal communities in 3 southern islands of Changshan archipelago were studied . The results showed that the community appearance and structure in rocky intertidal zones of 3 islands were regimented by dominant species Chthamalus challengeri, Ostrea spp., macro-algae and Littorina brevicula, while in gravel intertidal zones of Southern Changshan and Daheishan regimented by Chthamalus challengeri, Littorina brevicula, Ostrea spp., and in Northern Changshan, by Chthamalus challengeri, macro-algae and Gaetice depressus . There existed no obvious difference in community structures of rocky intertidal zones among 3 islands, which was demonstrated by the similarity in first 5 dominant species and their dominance ranks in the community . However, a significant difference was achieved in gravel intertidal communities, in which, the dominant species in the community at Northern Changshan differed greatly from that of others . The community diversity in R, J, D(B), D(IV), H(B), and H(IV), in rocky intertidal communities among 3 islands showed a great coincidence, Northern Changshan > Southern Changshan > Daheishan, however, little coincident results were found among gravel intertidal communities . It was found that there existed a higher community diversity in gravel intertidal communities at Daheishan and Southern Changshan than at Northern Changshan where existed the highest species evenness . The community diversity was generally higher in gravel intertidal communities than in rocky intertidal ones . The variation in community compositions, structures and diversities were resulted mainly from topographical heterogeneities, substratum heterogeneities, hydrodynamics, water eutrophication and human disturbance in intertidal zones.

Huan Jing Ke Xue, 2003 May, 24(3), 96 - 100
{Minimum application rates for high-yielding rice production system in the Taihu Lake region as a field measure for controlling N and P agricultural loading}; Pan G et al.; Excess application with the poor efficiency of fertilizers is one of the major problems confronting the sustainable agricultural development . Whereas, loss of N and P nutrients from farmlands to surface waters is considered as one of the major sources inducing eutrophication . In order to work out a minimum fertilizer application rate for both keeping conventional yield and reducing nutrient loading of non point source pollution, an experiment of formulated fertilization scheme on rice at different rates and nutrient ratios by incorporating the soil supply potential was conducted in a paddy soil Wunitu in Kunshan City, Suzhou . The soil nutrient can supply a yield at 6.75 t/hm2 at least for one cropping season . Among the fertilization treatments, a maximum yield of 9.79 t/hm2 was obtained at fertilization (N + P) rate of 300 kg/hm2kg N and P at a ratio of N to P being 3:2 or 1:1 . However, with much lower fertilization (N + P) rate at 240 kg/hm2 with the same ratio a high yield of 9.69 t/hm2 was reached . The fertilizer efficiency of the later was 3 times as that of the former rate . Thus, a economical and environmentally sound mode of fertilization in such paddy soils as total N and P 240 kg/hm2, with N:P:Kratio being 3:2:0 or 1:1:0 was developed . Further study would be directed to a innovation of combination of reducing fertilization rate with rotated fertilization for alternative crops.

J Ind Microbiol Biotechnol, 2003 Jul, 30(7), 383 - 406 Epub 2003 Jul 30.
Harmful algal blooms: causes, impacts and detection; Sellner KG et al.; Blooms of autotrophic algae and some heterotrophic protists are increasingly frequent in coastal waters around the world and are collectively grouped as harmful algal blooms (HABs) . Blooms of these organisms are attributed to two primary factors: natural processes such as circulation, upwelling relaxation, and river flow; and, anthropogenic loadings leading to eutrophication . Unfortunately, the latter is commonly assumed to be the primary cause of all blooms, which is not the case in many instances . Moreover, although it is generally acknowledged that occurrences of these phenomena are increasing throughout the world's oceans, the reasons for this apparent increase remain debated and include not only eutrophication but increased observation efforts in coastal zones of the world . There is a rapidly advancing monitoring effort resulting from the perception of increased impacts from these HABs, manifested as expanding routine coastal monitoring programs, rapid development and deployment of new detection methods for individual species, toxins, and toxicities, and expansion of coastal modeling activities towards observational forecasts of bloom landfall and eventually bloom prediction . Together, these many efforts will provide resource managers with the tools needed to develop effective strategies for the management and mitigation of HABs and their frequently devastating impacts on the coastal environment.

Ann Occup Hyg, 2003 Aug, 47(6), 441 - 59
Technical, occupational health and environmental aspects of metal degreasing with aqueous cleaners; Lavoue J et al.; Aqueous cleaners used for metal degreasing are detergent formulations containing surfactants (such as linear alkylbenzene sulphonates, alkylphenol ethoxylates or alcohol ethoxylates), builders (such as hydroxides, phosphates or silicates), sequestrants (such as EDTA or NTA), anti-corrosive agents (such as ethanolamines), solvents (such as glycol ethers or d-limonene) and other specialty additives . Generally sold as concentrates, they are typically diluted between 3 and 20 times in water, leading to solutions containing only a few per cent active products . The cleaning efficiency depends on physicochemical phenomena such as wetting, solubilization, emulsification, dispersion, sequestration and saponification, and is enhanced by thermal and mechanical energy . Cleaning equipment is based on spraying or immersion of the parts and may include drying and rinsing steps . Because of the complexity and variability of the mixtures, the occupational health and environmental evaluation of aqueous cleaners is based on the study of their components . Aqueous cleaners are generally believed to present a low risk to workers' health and to the environment . However, some anionic surfactants and strong alkalis are skin and eye irritants, ethanolamines are allergenic and several glycol ethers of the ethylene glycol family are proven systemic toxicants that are easily absorbed through the skin . Although most components of aqueous cleaners are biodegradable and of low ecotoxicity, alkylphenol ethoxylates degrade into persistent and toxic compounds . Phosphates, if released directly into the environment, may cause eutrophication of rivers and lakes . Waste recycling or treatment by specialized facilities is usually required for spent solutions containing contaminants such as oils and heavy metals . From a technical, toxicological and environmental standpoint, aqueous cleaners can be used successfully to replace traditional organic solvents used in metal degreasing.

Sci Total Environ, 2003 Aug 1, 312(1-3), 221 - 43
Multiplatform optical monitoring of eutrophication in temporally and spatially variable lakes; Vos RJ et al.; Representative spatial patterns of eutrophication variables cannot be produced using traditional in situ sampling techniques . Spatial heterogeneity complicates the study of seasonal and long-term trends and the evaluation of water management policies . Remote sensing, however, with its broad view has the potential to deliver the relevant information . This paper will address the added value of synoptic eutrophication maps to the standard monitoring program of two large, spatially and temporally variable lakes in the Netherlands, Lakes IJssel and Marken . Remote sensing images were obtained from SeaWiFS; and combined with hyperspectral reflectance data from the airborne EPS-a sensor and the shipboard PR-650 spectroradiometer . The PR-650 data were used in selecting the most appropriate algorithms for SeaWiFS and EPS-a . A special algorithm for case II waters with high chlorophyll content was applied to SeaWiFS data to obtain chlorophyll concentrations . Synoptic maps of suspended matter were retrieved using inversion of a model for irradiance reflectance . For the airborne sensor inversion of reflectance was used for both suspended matter and chlorophyll . Satellite and airborne sensors clearly are complementary to each other . Comparison of satellite data with the airborne data and the (scarcely available) in situ data reveal underlying problems with: (i) validation of remote sensing images; and (ii) comparing data at different spatial and temporal scales . In our study, we found a reasonable agreement between different data sources at seasonal time scales, but at shorter time scales the differences can be (much) larger . In situ data suffer from poor reproducibility, related to the natural variability at small spatial scales (patchiness), combined with a significant temporal variability . The standard in situ monitoring program in Lakes IJssel and Marken lacks both the necessary spatial coverage as well as an appropriate sampling frequency . This indicates that for reliable monitoring, a synoptic data set, sampled at a high frequency is required . Remote sensing can partially fulfil this demand but still lacks the demanded frequency, mainly due to regular cloud cover . The answer may be in a multiplatform monitoring approach, as used in our study (combining in situ data with shipboard, airborne and satellite optical data) and in combining monitoring data with models . Satellite remote sensing is most powerful in determining properties that are inherent to the whole lake system, like the overall mean chlorophyll-a concentration . Computational models may meet the demand for a sufficiently high sampling frequency by deterministic interpolation of the data in time.

Mar Pollut Bull, 2003 Jul, 46(7), 858 - 64
Comparison of coral growth and survival under enclosed, semi-natural conditions and in the field; Yap HT et al.; Two closely related scleractinian coral species, Porites cylindrica and Porites rus, were transplanted to two different locations: the natural environment on the reef flat, and culture tanks on land . The use of tanks enabled the regulation of certain environmental factors, and, hence, the evaluation of specific responses of the corals to these factors . For both species, growth and survival were much better in the field than in the land-based tanks most probably due to unrestricted water circulation . Since the two species were subjected to identical experimental treatments, it was possible to distinguish inherent differences between them in terms of responses to external variables . Porites cylindrica was more susceptible than P . rus to predation by corallivores . Predators, as well as grazers, occurred in significant numbers in the field, but not in the land-based tanks . Porites rus, on the other hand, succumbed more readily to overgrowth by macroalgae which thrived in the culture tanks presumably because of significantly higher nutrient levels and the conspicuous absence of grazers . These results have broader ecological implications because of accelerated environmental changes taking place in present-day reefs due to human impact . Major examples are eutrophication and alterations in water circulation which frequently result in sub-optimal conditions for coral survival and growth.

Fish Shellfish Immunol, 2003 Aug, 15(2), 159 - 68
The effect of dietary phosphorus deficiency on the immune responses of European whitefish (Coregonus lavaretus L.); Jokinen EI et al.; Low phosphorous (P) feeds in aquaculture are recommended to reduce eutrophication of water systems . However, the feed should be adequate for normal growth and intact immune defence . Influence of low dietary P supply on non-specific and specific immune defence of European whitefish (Coregonus lavaretus) was studied in two trials . For Trial 1, a semi-purified, low-P diet was formulated and supplied with 0, 2.5, 5.0, 7.5, or 10.0 g P kg(-1)to obtain a P gradient of 4.4-14.9 g kg(-1)diet . Diets were fed to four replicate groups of fingerling whitefish for 42 days in a flow-through, freshwater system maintained at 15 degrees C . Fish fed with the P-unsupplemented diet had significantly lower plasma immunoglobulin M (IgM) levels than fish fed with the P-fortified diets (means 2.53 vs . 3.19 mg ml(-1); P=0.047) . Plasma lysozyme activity did not differ between fish fed with the P-unsupplemented diet and fish fed with the P-fortified diets (means 21.8 vs . 25.5 U ml(-1); P=0.107) . For Trial 2, fish were acclimated for 49 days by feeding the lowest or highest dietary P contents, and thereafter immunised with a single intraperitoneal injection of a novel antigen, bovine gamma globulin (BGG) . A clear antibody response against BGG was elicited but the antibody levels did not differ between fish fed low-P or high-P contents . Similar to Trial 1, plasma IgM was lower in fish fed low-P diets, and low-P diet did not influence plasma lysozyme activity . In both trials the growth of fish, having received low-P diet, was significantly lowered . It is concluded that P deficiency has only minor effects on the immune parameters in whitefish, and the practical aquafeed with P contents sufficient for normal growth does not compromise immune functions of this species.

Environ Sci Technol, 2003 Jun 1, 37(11), 2600 - 8
Evaluating uncertainty in environmental life-cycle assessment . A case study comparing two insulation options for a Dutch one-family dwelling; Huijbregts MA et al.; The evaluation of uncertainty is relatively new in environmental life-cycle assessment (LCA) . It provides useful information to assess the reliability of LCA-based decisions and to guide future research toward reducing uncertainty . Most uncertainty studies in LCA quantify only one type of uncertainty, i.e., uncertainty due to input data (parameter uncertainty) . However, LCA outcomes can also be uncertain due to normative choices (scenario uncertainty) and the mathematical models involved (model uncertainty) . The present paper outlines a new methodology that quantifies parameter, scenario, and model uncertainty simultaneously in environmental life-cycle assessment . The procedure is illustrated in a case study that compares two insulation options for a Dutch one-family dwelling . Parameter uncertainty was quantified by means of Monte Carlo simulation . Scenario and model uncertainty were quantified by resampling different decision scenarios and model formulations, respectively . Although scenario and model uncertainty were not quantified comprehensively, the results indicate that both types of uncertainty influence the case study outcomes . This stresses the importance of quantifying parameter, scenario, and model uncertainty simultaneously . The two insulation options studied were found to have significantly different impact scores for global warming, stratospheric ozone depletion, and eutrophication . The thickest insulation option has the lowest impact on global warming and eutrophication, and the highest impact on stratospheric ozone depletion.

Water Sci Technol, 2003, 47(9), 85 - 92
A set of marine microalgae bioassays for the evaluation of biological water quality in enclosure areas in south of Spain; Garrido-Perez MC et al.; The aim of this study has been the identification of the nutritive status (oligotrophy end eutrophy) in four enclosure areas from Gulf of Cadiz (Southwest Iberian Peninsula-Europe) by means of a battery of water column toxicity tests . The test organisms were four marine microalgae which comprised a wide taxonomic range . Growth tests with receiving waters from the four study areas were carried out under two nutritive conditions; with and without additional nutrient-enriched medium . The results of both bioassays were used to define a new eutrophication index (I(E)) . The I(E) index obtained presents a good correlation with the traditional physical-chemical parameters in the enclosure areas; nevertheless in open waters where the dilution processes are more important the results show less correlation.

Ying Yong Sheng Tai Xue Bao, 2003 Feb, 14(2), 277 - 9
{Purification of eutrophicated water body by Vetiveria zizanioids}; Si Y et al.; Studies on the purification efficiency of eutrophicated water body by Vetiveria Zizanioids on floating-beds showed that V . zizanioids had a great ability to remove TN, NH4(+)-N, TP, PO4(3-), COD, and BOD, and had a significant effect on improving water quality . It was proved that V . zizanioids could be used to purify the eutrophicated water body.

Ying Yong Sheng Tai Xue Bao, 2003 Feb, 14(2), 196 - 200
{Dynamics of upland field P pool under a long-term application of fertilizer P in yellow soil area and their effects on P concentration in runoff}; Liu F et al.; Studies on the dynamics of upland field P pool under a long-term application of fertilizer P in yellow soil area and their effects on P concentration in runoff showed that the contents of A1-P, Fe-P and Ca-P in soil cultivated layer increased greatly, and Olsen-P and algae-available P also accumulated obviously . The correlation coefficients of algae-available P content in the high-P soils (Olsen-P > 25 mg.kg-1) with the quantities of A1-P, Fe-P and Ca-P were 0.859**, 0.903** and 0.650*, respectively, of which, Fe-P was the most important . By a 30-min rainfall simulation experiment with a constant rainfall rate of 63.2 mm.h-1, the concentrations of dissolved reactive P and bio-available P in runoff from low-P upland fields (Olsen-P 4.62-15.9 mg.kg-1) were 2.81-4.17 micrograms.L-1 and 0.723-0.876 mg.L-1, respectively, whereas their concentrations in runoff from high-P upland fields (Olsen-P 29.4-59.2 mg.kg-1) were 0.026-0.714 mg.L-1 and 0.996-1.281 mg.L-1, respectively . Therefore, runoff from high-P upland fields could accelerate water eutrophication.

Environ Pollut, 2003, 125(3), 433 - 46
Effect of eutrophication upon radionuclide dynamics in the Sacca di Goro lagoon (Po River Delta, Italy): a combined field, experimental and modeling study; Bondavalli C; The focus of this paper is on the relationship between eutrophication and radionuclide circulation at the whole ecosystem scale in the shallow estuarine environment of the Sacca di Goro (Po River Delta, Italy) . This lagoon is frequently affected by dystrophic crises, due to decomposition of huge amounts of macroalgae (mainly Ulva rigida), and critical conditions created at the interface between sediment and water are such that Cs-137 accumulated in the sediment can be mobilized and made available in the water column . The release of cesium from sediment in this ecosystem has been evaluated through a field experiment in which chemical conditions typical of anoxic crises were artificially created in enclosures . Also a lab experiment was carried out to shed light on possible cesium release by decomposing macroalgae . The two experiments allowed drawing conclusions on crucial factors controlling cesium release in the Sacca di Goro, the first objective of this research . The second objective was understanding the fate of radiocesium once transported in the water column . To this end ecological information gathered during the experiments and a yearly sampling campaign, has been converted into whole-system seasonal networks describing ecosystem flow structure for the Sacca di Goro . Analyzed by network analysis this model has provided clues about the dynamics of Cs-137 in terms of preferential pathways, sinks, sources, and cycling activity . Sediment, together with seston and dissolved cesium, appear to be the most significant components in the circulation of Cs-137; while macroalgal biomasses play a crucial role as an indirect causal factor.

Ann Ist Super Sanita, 2003, 39(1), 3 - 10
{Evaluation of pollution load in marine coastal waters}; Pagnotta R et al.; The potential pollution loads, of both organic and eutrophicating type, along the Italian coast were evaluated with reference to census data of 1991 . The methodology adopted for the indirect evaluation of loads are those developed by the Water Research Institute of the Italian National Research Council . They take into account the different sources of pollution load, namely population, industry, agriculture and cattle farming . Pollution loads were estimated at coastal provinces level . Annual riverine fluxes of pollutants were also evaluated for the main Italian rivers . Finally, the positive role played by the adoption of monitoring plans forecasted by the national law recently come into force (DL.vo 152/99) for a better evaluation of the pollution loads was stressed.

Environ Pollut, 2003, 125(2), 117 - 22
Short term dynamics of diatoms in an upland stream and implications for monitoring eutrophication; Kelly MG; A study designed to examine the effect of intermittent diffuse nutrient inputs on diatom assemblages in a small upland stream in northern England was confounded by other changes that occurred in the stream just before fertilisation started . A flora dominated by attached diatoms changed, over a period of about 3 weeks to one dominated by motile Nitzschia spp . In the absence of any likely human causes, the most likely reason for this change was undercutting of a meander upstream, releasing fine silts which favoured motile diatoms . Changes due to fertilisation by phosphorus were also recorded, with an increase in the proportion of Epithemia in samples, possibly favoured by the lower N:P ratio caused by the increased P concentration . The implication of these changes for monitoring eutrophication and ecological status in upland streams is discussed.

J Environ Qual, 2003 May-Jun, 32(3), 1082 - 8
Estimating soil phosphorus requirements and limits from oxalate extract data; D'Angelo EM et al.; Excessive fertilizer and manure phosphorus (P) inputs to soils elevates P in soil solution and surface runoff, which can lead to freshwater eutrophication . Runoff P can be related to soil test P and P sorption saturation, but these approaches are restricted to a limited range of soil types or are difficult to determine on a routine basis . The purpose of this study was to determine whether easily measurable soil characteristics were related to the soil phosphorus requirements (P(req), the amount of P sorbed at a particular solution P level) . The P(req) was determined for 18 chemically diverse soils from sorption isotherm data (corrected for native sorbed P) and was found to be highly correlated to the sum of oxalate-extractable Al and Fe (R2 > 0.90) . Native sorbed P, also determined from oxalate extraction, was subtracted from the P(req) to determine soil phosphorus limits (PL, the amount of P that can be added to soil to reach P(req)) . Using this approach, the PL to reach 0.2 mg P L(-1) in solution ranged between -92 and 253 mg P kg(-1) . Negative values identified soils with surplus P, while positive values showed soils with P deficiency . The results showed that P, Al, and Fe in oxalate extracts of soils held promise for determining PL to reach up to 10 mg P L(-1) in solution (leading to potential runoff from many soils) . The soil oxalate extraction test could be integrated into existing best management practices for improving soil fertility and protecting water quality.

J Environ Qual, 2003 May-Jun, 32(3), 1072 - 81
Effect of broadcast manure on runoff phosphorus concentrations over successive rainfall events; Kleinman PJ et al.; Concern over eutrophication has directed attention to manure management effects on phosphorus (P) loss in runoff . This study evaluates the effects of manure application rate and type on runoff P concentrations from two, acidic agricultural soils over successive runoff events . Soils were packed into 100- x 20- x 5-cm runoff boxes and broadcast with three manures (dairy, Bos taurus, layer poultry, Gallus gallus; swine, Sus scrofa) at six rates, from 0 to 150 kg total phosphorus (TP) ha(-1) . Simulated rainfall (70 mm h(-1)) was applied until 30 min of runoff was collected 3, 10, and 24 d after manure application . Application rate was related to runoff P (r2 = 0.50-0.98), due to increased concentrations of dissolved reactive phosphorus (DRP) in runoff; as application rate increased, so did the contribution of DRP to runoff TP . Varied concentrations of water-extractable phosphorus (WEP) in manures (2-8 g WEP kg(-1)) resulted in significantly lower DRP concentrations in runoff from dairy manure treatments (0.4-2.2 mg DRP L(-1)) than from poultry (0.3-32.5 mg DRP L(-1)) and swine manure treatments (0.3-22.7 mg DRP L(-1)) . Differences in runoff DRP concentrations related to manure type and application rate were diminished by repeated rainfall events, probably as a result of manure P translocation into the soil and removal of applied P by runoff . Differential erosion of broadcast manure caused significant differences in runoff TP concentrations between soils . Results highlight the important, but transient, role of soluble P in manure on runoff P, and point to the interactive effects of management and soils on runoff P losses.

J Environ Qual, 2003 May-Jun, 32(3), 1044 - 52
Phosphorus loss to runoff water twenty-four hours after application of liquid swine manure or fertilizer; Tabbara H; Phosphorus (P) added to soil from fertilizer or manure application could pose a threat to water quality due to its role in eutrophication of fresh water resources . Incorporating such amendments into the soil is an established best management practice (BMP) for reducing soluble P losses in runoff water, but could also lead to higher erosion . The objective of this study was to test whether incorporation of manure or fertilizer 24 h before an intense rain could also reduce sediment-bound and total phosphorus (TP) losses in runoff . A rainfall simulation study was conducted on field plots (sandy loam with 6-7% slope, little surface residue, recently cultivated) that received two application rates of liquid swine manure or liquid ammonium polyphosphate fertilizer, using either surface-broadcast or incorporated methods of application . Incorporation increased the total suspended solids (TSS) concentrations in runoff but mass losses were not affected . Incorporation also reduced flow-weighted concentrations and losses of dissolved reactive phosphorus (DRP) and TP by as much as 30 to 60% depending on source (fertilizer vs . manure) and application rate . Phosphorus is moved below the mixing zone of interaction on incorporation, and thus the effect of the amount and availability of P in this zone is more important than cultivation on subsequent P losses in runoff . Incorporating manure or fertilizer in areas of intense erosive rain, recent extensive tillage, and with little or no surface residue is therefore a best management practice that should be adhered to in order to minimize contamination of surface water . Results also show comparatively lower P losses from manure than fertilizer.

ScientificWorldJournal, 2001 Jul 17, 1, 254 - 63
Alternative attractors of shallow lakes; Scheffer M; Ponds and shallow lakes can be very clear with abundant submerged plants, or very turbid due to a high concentration of phytoplankton and suspended sediment particles . These strongly contrasting ecosystem states have been found to represent alternative attractors with distinct stabilizing feedback mechanisms . In the turbid state, the development of submerged vegetation is prevented by low underwater light levels . The unprotected sediment frequently is resuspended by wave action and by fish searching for food causing a further decrease of transparency . Since there are no plants that could serve as refuges, zooplankton is grazed down by fish to densities insufficient to control algal blooms . In contrast, the clear state in eutrophic shallow lakes is dominated by aquatic macrophytes . The submerged macrophytes prevent sediment resuspension, take up nutrients from the water, and provide a refuge for zooplankton against fish predation . These processes buffer the impacts of increased nutrient loads until they become too high . Consequently, the response of shallow lakes to eutrophication tends to be catastrophic rather than smooth, and various lakes switch back and forth abruptly between a clear and a turbid state repeatedly without obvious external forcing . Importantly, a switch from a turbid to a stable clear state often can be invoked by means of biomanipulation in the form of a temporary reduction of the fish stock.

ScientificWorldJournal, 2001 Oct 27, 1 Suppl 2, 860 - 5
Managing ammonia emissions from dairy cows by amending slurry with alum or zeolite or by diet modification; Meisinger JJ et al.; Animal agriculture is a significant source of atmospheric ammonia . Ammonia (NH3) volatilization represents a loss of plant available N to the farmer and a potential contributor to eutrophication in low-nitrogen input ecosystems . This research evaluated on-farm slurry treatments of alum or zeolite and compared three diets for lactating dairy cows in their effectiveness to reduce NH3 emissions . NH3 emissions were compared using a group of mobile wind tunnels . The addition of 2.5% alum or 6.25% zeolite to barn-stored dairy slurry reduced NH3 volatilization by 60% and 55%, respectively, compared to untreated slurry . The alum conserved NH3 by acidifying the slurry to below pH 5, while the zeolite conserved ammonia by lowering the solution-phase nitrogen through cation exchange . The use of alum or zeolite also reduced soluble phosphorus in the slurry . NH3 loss from fresh manure collected from lactating dairy cows was not affected by three diets containing the same level of crude protein but differing in forage source (orchardgrass silage vs . alfalfa silage) or neutral detergent fiber (NDF) content (30% vs . 35% NDF) . NH3 losses from the freshly excreted manures occurred very rapidly and included the urea component plus some unidentified labile organic nitrogen sources . NH3 conservation strategies for fresh manures will have to be active within the first few hours after excretion in order to be most effective . The use of alum or zeolites as an on-farm amendment to dairy slurry offers the potential for significantly reducing NH3 emissions.

ScientificWorldJournal, 2001 Oct 30, 1 Suppl 2, 814 - 21
Cost-effective emission abatement in europe considering interrelations in agriculture; Brink C et al.; Agriculture is an important source of ammonia (NH3), which contributes to acidification and eutrophication, as well as emissions of the greenhouse gases nitrous oxide (N2O) and methane (CH4) . Controlling emissions of one of these pollutants through application of technical measures might have an impact (either beneficial or adverse) on emissions of the others . These side effects are usually ignored in policy making . This study analyses cost-effectiveness of measures to reduce acidification and eutrophication as well as agricultural emissions of N2O and CH4 in Europe, taking into account interrelations between abatement of NH3, N2O, and CH4 in agriculture . The model used is based on the RAINS (Regional Air pollution INformation and Simulation) model for air pollution in Europe, which includes emissions, abatement options, and atmospheric source-receptor relationships for pollutants contributing to acidification and eutrophication . We used an optimisation model that is largely based on the RAINS model but that also includes emissions of N2O and CH4 from agriculture and technical measures to reduce these emissions . For abatement options for agricultural emissions we estimated side effects on other emissions . The model determines abatement strategies to meet restrictions on emission and/or deposition levels at the least cost . Cost-effective strategies to reduce acidification and eutrophication in Europe were analysed . We found that NH3 abatement may cause an increase in N2O emissions . If total agricultural N2O and CH4 emissions in Europe were not allowed to increase, cost-effective allocation of emission reductions over countries in Europe changed considerably.

ScientificWorldJournal, 2001 Oct 26, 1 Suppl 2, 371 - 7
Nitrogen and the Baltic Sea: managing nitrogen in relation to phosphorus; Elmgren R et al.; The Baltic is a large, brackish sea (4 x 10(5) km2) extending from 54N to approximately 66N, with a fourfold larger drainage area (population 8 x 10(7) . Surface salinity (2 to 8 PSU) and hence biodiversity is low . In the last century, annual nutrient loads increased to 10(6) metric tons N and 5 x 10(4) ton P . Eutrophication is evident in the N-limited south, where cyanobacteria fix 2 to 4 x 10(5) ton N each summer, Secchi depths have been halved, and O2-deficient bottom areas have spread . Production remains low in the P-limited north . In nutrient-enriched coastal areas, phytoplankton blooms, toxic at times, and filamentous macroalgae reduce amenity values . Loads need to be reduced of both N, to reduce production, and P, to limit N-fixing cyanobacterial blooms . When large N-load reductions have been achieved locally, algal biomass has declined . So far, P loads have been reduced more than N loads . If this continues, a P-limited Baltic proper may result, very different from previous N-limited conditions . Reaching the management goal of halved anthropogenic N and P loads at minimum cost will require better understanding of biogeochemical nutrient cycles, economic evaluation of proposed measures, and improved stakeholder participation.

ScientificWorldJournal, 2001 Oct 03, 1 Suppl 2, 255 - 60
A new approach to determine the total airborne N input into the soil/plant system using 15N isotope dilution (ITNI): results for agricultural areas in Central Germany; Russow RW et al.; The atmospheric deposition of nitrogen (N) in the environment is of great concern due to its impact on natural ecosystems including affecting vegetation, reducing biodiversity, increasing tree growth in forests, and the eutrophication of aquatic systems . Taking into account the average annual N emission into the atmosphere in Germany of about 2 million t N (ammonia/ammonium, NOx), and assuming homogeneous distribution throughout Germany, an average N deposition of 45 kg/ha x year can be calculated . Such high atmospheric N deposition could be confirmed by N balances from long-term field experiments in Central Germany (e.g., the Static Fertilization Experiment in Bad Lauchstdt) . By contrast, estimates by standard methods indicate a deposition of only about 30 kg N/ha x year . This is because the standard methods are using wet-only or bulk collectors, which fail to take into account gaseous deposition and the direct uptake of atmospheric N by aerial plant parts . Therefore, a new system was developed using 15N isotope dilution methodology to measure the actual total atmospheric N input into a soil/plant system (Integrated Total Nitrogen Input, ITNI) . A soil/plant system is labeled with {15N}ammonium-{15N}nitrate and the total input of airborne N is calculated from the dilution of this tracer by N from the atmosphere . An average annual deposition of 64 +/- 11 kg/ha x year from 1994-2000 was measured with the ITNI system at the Bad Lauchstdt research farm in the dry belt of Central Germany . Measurements in 1999/2000 at three other sites in Central Germany produced deposition rates of about 60 kg/ha x year . These data clearly show that the total atmospheric N deposition into the soil/plant system determined by the newly developed ITNI system significantly exceeds that obtained from standard wet-only and bulk collectors . The higher atmospheric N depositions found closely match those postulated from the N balances of long-term agricultural field experiments.

ScientificWorldJournal, 2001 Nov 14, 1 Suppl 2, 945 - 52
Past and future exceedances of nitrogen critical loads in Europe; Posch M et al.; Critical loads of acidity and nutrient nitrogen--simple measures of the sensitivity of ecosystems to deposition--have been widely used for setting emission reduction targets in Europe . In contrast to sulfur, the emissions of nitrogen compounds remain high in the future . This is also true for the exceedances of critical loads until 2010 . Looking further into the future, climate change is likely to influence ecosystem sensitivity, and thus critical loads . It is shown that higher temperatures, changed precipitation patterns, and modified net primary production mainly increase critical loads, except in mountainous and arid regions . Using consistent scenarios of climate change and air pollution from a recently completed European study (AIR-CLIM), it is shown that the exceedances in 2100 of the critical loads are declining in comparison to 2010 . However, exceedances of critical loads of nutrient nitrogen remain substantial, even under the most stringent scenario . This confirms the increasing role nitrogen plays in environmental problems in comparison to sulfur . Thus research should focus on the effects of nitrogen in the environment, especially under conditions of climate change, to support nitrogen-emission mitigating policies . This not only reduces acidification and eutrophication, but also helps curb the formation of tropospheric ozone.

ScientificWorldJournal, 2001 Nov 09, 1 Suppl 2, 898 - 907
Assessment of nitrogen ceilings for Dutch agricultural soils to avoid adverse environmental impacts; de Vries W et al.; In the Netherlands, high traffic density and intensive animal husbandry have led to high emissions of reactive nitrogen (N) into the environment . This leads to a series of environmental impacts, including: (1) nitrate (NO3) contamination of drinking water, (2) eutrophication of freshwater lakes, (3) acidification and biodiversity impacts on terrestrial ecosystems, (4) ozone and particle formation affecting human health, and (5) global climate change induced by emissions of N2O . Measures to control reactive N emissions were, up to now, directed towards those different environmental themes . Here we summarize the results of a study to analyse the agricultural N problem in the Netherlands in an integrated way, which means that all relevant aspects are taken into account simultaneously . A simple N balance model was developed, representing all crucial processes in the N chain, to calculate acceptable N inputs to the farm (so-called N ceiling) and to the soil surface (application in the field) by feed concentrates, organic manure, fertiliser, deposition, and N fixation . The N ceilings were calculated on the basis of critical limits for NO 3 concentrations in groundwater, N concentrations in surface water, and ammonia (NH3) emission targets related to the protection of biodiversity of natural areas . Results show that in most parts of the Netherlands, except the western and the northern part, the N ceilings are limited by NH 3 emissions, which are derived from critical N loads for nature areas, rather than limits for both ground- and surface water . On the national scale, the N ceiling ranges between 372 and 858 kton year(-1) depending on the choice of critical limits . The current N import is 848 kton year(-1) . A decrease of nearly 60% is needed to reach the ceilings that are necessary to protect the environment against all adverse impacts of N pollution from agriculture.

ScientificWorldJournal, 2001 Nov 15, 1 Suppl 2, 520 - 6
Nitrogen deposition and leaching from two forested catchments in Southwest China--preliminary data and research needs; Larssen T et al.; Increased nitrogen deposition has resulted in increased nitrogen pools and nitrogen leaching in European and North American forest soils . The development in Asia in general, and China in particular, suggests increased deposition of reduced nitrogen from changes in agricultural practices and of oxidized nitrogen from rapid growth of the transportation sector . Decreased nitrogen retention in forested areas in the future may cause increased NO3- leaching and, thus, acidification and eutrophication in surface waters . The differences in climate, ecosystems, land use, and deposition history make direct application of knowledge from studies in Europe and North America difficult . In Southwest China the potential for nitrogen mobilization from forest soils may be high because of the warm and humid climate, resulting in high decomposition rates of soil organic matter . However, there are very few data available for quantifying the suspected potential for increased nitrogen leaching in forest ecosystems . Here we present data from two forested catchments, dominated by Masson pine (Pinus massoniana), near Guiyang and Chongqing, respectively, in Southwest China . The present nitrogen deposition is moderate, estimated in the range from 10 to 40 kg N ha(-1) year(-1) . The C/N ratios of the soils are generally below 15 . Nitrate concentrations in soil water are rather variable in space, with highest values of several hundred microequivalents per liter . The turnover rate of nitrogen in the forest ecosystem is quite high compared to the atmospheric deposition rate . At present, nitrate runoff from the catchments is low and intermediate in Guiyang and Chongqing, respectively . More research is needed to improve our ability to predict future nitrogen leaching from subtropical Asian coniferous forests.

ScientificWorldJournal, 2001 Nov 28, 1 Suppl 2, 275 - 86
A spatial analysis of atmospheric ammonia and ammonium in the U.K; Sutton MA et al.; As measures are implemented internationally to reduce SO2 and NOx emissions, attention is falling on the contribution of NH3 emissions to acidification, nitrogen eutrophication, and aerosol formation . In the U.K., a monitoring network has been established to measure the spatial distribution and long-term trends in atmospheric gaseous NH3 and aerosol NH4+ . At the same time, an atmospheric chemistry and transport model, FRAME, has been developed with a focus on reduced nitrogen (NHx) . The monitoring data are important to evaluate the model, while the model is essential for a more detailed spatial assessment . The national network is established with over 80 sampling locations . Measurements of NH3 and NH4+ (at up to 50 sites) have been made using a new low-cost denuder-filterpack system . Additionally, improved passive sampling methods for NH3 have been applied to explore local variability . The measurements confirm the high spatial variability of NH3 (annual means 0.06 to 11 microg NH3 m(-3)), consistent with its nature as a primary pollutant emitted from ground-level sources, while NH4+, being a slowly formed secondary product, shows much less spatial variability (0.14 to 2.4 mg NH4+ m(-3)) . These features are reproduced in the FRAME model, which provides estimates at a 5-km level . Analysis of the underlying NH3 emission inventory shows that sheep emissions may have been underestimated and nonagricultural sources overestimated relative to emissions from cattle . The combination of model and measurements is applied to estimate spatial patterns of dry deposition to different vegetation types . The combined approach provides the basis to assess NHx responses across the U.K . to international emission controls.

ScientificWorldJournal, 2001 Nov 17, 1 Suppl 2, 194 - 9
Partial validation of the Dutch model for emission and transport of nutrients (STONE); Overbeek GB et al.; The Netherlands has to cope with large losses of N and P to groundwater and surface water . Agriculture is the dominant source of these nutrients, particularly with reference to nutrient excretion due to intensive animal husbandry in combination with fertilizer use . The Dutch government has recently launched a stricter eutrophication abatement policy to comply with the EC nitrate directive . The Dutch consensus model for N and P emission to groundwater and surface water (STONE) has been developed to evaluate the environmental benefits of abatement plans . Due to the possibly severe socioeconomic consequences of eutrophication abatement plans, it is of utmost importance that the model is thoroughly validated . Because STONE is applied on a nationwide scale, the model validation has also been carried out on this scale . For this purpose the model outputs were compared with lumped results from monitoring networks in the upper groundwater and in surface waters . About 13,000 recent point source observations of nitrate in the upper groundwater were available, along with several hundreds of observations showing N and P in local surface water systems . Comparison of observations from the different spatial scales available showed the issue of scale to be important . Scale issues will be addressed in the next stages of the validation study.

ScientificWorldJournal, 2001 Dec 06, 1 Suppl 2, 936 - 44
Derivation and mapping of critical loads for nitrogen and trends in their exceedance in Germany; Nagel HD et al.; The term "critical load" means a quantitative estimate of an exposure to one or more pollutants below which significant harmful effects on specified sensitive elements of the environment do not occur, according to present knowledge . In the case of nitrogen, both oxidised and reduced compounds contribute to the total deposition of acidity, which exceeds critical loads in many forest ecosystems . These also cause negative effects through eutrophication . Critical loads of nitrogen were derived for forest soils (deciduous and coniferous forest), natural grassland, acid fens, heathland, and mesotrophic peat bogs . In Germany, a decrease in sulphur emissions over the past 15 years resulted in a reduced exceedance of critical loads for acid deposition . In the same period it was noted that reduction in the emissions of nitrogen oxides and ammonia remained insignificant . Therefore, emissions of nitrogen compounds have become relatively more important and will continue to threaten ecosystem function and stability . The risk of environmental damage remains at an unacceptable level . The German maps show the degree to which the critical loads are exceeded, and they present current developments and an expected future trend . Results indicate that recovery from pollutant stress occurs only gradually.

ScientificWorldJournal, 2001 Dec 19, 1 Suppl 2, 142 - 7
Alternate nitrogen amendments for organic fertilizers; Sridhar MK et al.; The use of compost or manure in agriculture as an organic source of nutrients is common in many tropical, developing countries like Nigeria . One of the drawbacks of such materials is their low nitrogen (N) content (=1% N) . Farmers commonly use chemical N fertilizers such as urea, calcium ammonium nitrate (CAN), and NPK formulations to obtain better crop growth and yield . These chemical supplements may have a negative impact on the environment through nitrate leaching into water, leading to eutrophication of surface waters that can affect public health . Gliricidia sepium, a fast-growing, tropical, perennial hedge plant was tested as a source of N in organo-mineral fertilizer formulations . Average nutrient content of Gliricidia is 3.8% N, 0.32% P, 1.8% K, 0.8% Ca, and 0.2% Mg . Using a sand culture and Amaranthus caudatus as a test crop, it was shown that amending commercial composts with 30% Gliricidia prunings would benefit many small-scale farmers and control environmental pollution.

ScientificWorldJournal, 2001 Apr 04, 1, 5 - 6
Modeling water resources: have we got it right?
Havens KE.
Aquatic scientists generally recognize that controlled experiments are required to establish cause-effect relationships (e.g., Havens and Aumen, 2000), and understanding ecological processes is key to accurately predicting complex ecosystem responses . However, resource managers may have at their disposal only a limited amount of observational data when faced with management decisions . Hence, there may be a tendency to use simple empirical models for decision making . An example of eutrophication management in lakes illustrates a pitfall of this approach when used independently of other scientific information.

Bioresour Technol, 2003 Sep, 89(3), 229 - 36
Struvite precipitation in anaerobic swine lagoon liquid: effect of pH and Mg:P ratio and determination of rate constant; Nelson NO et al.; Because of increased concern about surface water eutrophication from nutrient-enriched agricultural runoff, many swine producers are encouraged to decrease application rates of waste-based P . Precipitation and subsequent removal of magnesium ammonium phosphate (MgNH(4)PO(4) x 6H(2)O), commonly known as struvite, is a promising mechanism for N and P removal from anaerobic swine lagoon effluent . The objectives of this research were to (i) quantify the effects of adjusting pH and Mg:P ratio on struvite precipitation and (ii) determine the rate constant pH effect for struvite precipitation in anaerobic swine lagoon liquid . Concentrations of PO(4)-P in liquid from two anaerobic swine lagoons were determined after 24 h of equilibration for a pH range of 7.5-9.5 and Mg:P ratios between 1:1 and 1.6:1 . Struvite formation reduced the PO(4)-P concentration in the effluents to as low as 2 mgl(-1) . Minimum concentrations of PO(4)-P occurred between pH 8.9 and 9.25 at all Mg:P ratios . Struvite precipitation decreased PO(4)-P concentrations by 85% within 20 min at pH 9.0 for an initial Mg:P ratio of 1.2:1 . The rate of PO(4)-P decrease was described by a first-order kinetic model, with rate constants of 3.7, 7.9, and 12.3 h(-1) at pH 8.4, 8.7 and 9.0 respectively . Our results indicate that induced struvite formation is a technically feasible method to remove N and P from swine lagoon liquid and it may allow swine producers to recover nutrients for off-farm sale.

Water Sci Technol, 2003, 47(7-8), 217 - 25
The Three Rivers Project--water quality monitoring and management systems in the Boyne, Liffey and Suir catchments in Ireland; Earle JR; The "Three Rivers Project" is a government initiative and one of a series of catchment based water quality monitoring and management systems being developed throughout Ireland since 1997 . The establishment of these multi-sectoral, basin-wide and community based systems is a response to historically perceived disjointed, legalistic and non-participative approaches to water resource management and purports to transcend the restrictions of traditional local authority administrative boundaries . The new management model embodies the concepts and objectives contained in the European Union (EU) Water Framework Directive (WFD) enacted in December 2000 . Ireland, in common with many EU countries, has failed to halt decades of increasing levels of eutrophication of surface waters due principally to phosphorus loading . The "Three Rivers Project" is promoting the benefits of an integrated and cooperative approach to the management of three important river systems in Ireland, namely, the Boyne, Liffey and Suir . The project objective is to protect and improve water quality to conform with "good ecological status" . The implications of the Project findings for agricultural, municipal and industrial policy are grave and one of the greatest challenges now is to organise and fund Irish River Basin Management Systems as envisaged by the WFD to continue and build on the work which the "Three Rivers Project" has undertaken.

Mar Pollut Bull, 2003, 47(1-6), 211 - 8
Set-up of a decision support system to support sustainable development of the Laguna de Bay, Philippines; Nauta TA et al.; Over recent decades, population expansion, deforestation, land conversion, urbanisation, intense fisheries and industrialisation have produced massive changes in the Laguna de Bay catchment, Philippines . The resulting problems include rapid siltation of the lake, eutrophication, inputs of toxics, flooding problems and loss of biodiversity . Rational and systematic resolution of conflicting water use and water allocation interests is now urgently needed in order to ensure sustainable use of the water resources . With respect to the competing and conflicting pressures on the water resources, the Laguna Lake Development Authority (LLDA) needs to achieve comprehensive management and development of the area . In view of these problems and needs, the Government of the Netherlands was funding a two-year project entitled 'Sustainable Development of the Laguna de Bay Environment'.A comprehensive tool has been developed to support decision-making at catchment level . This consists of an ArcView GIS-database linked to a state-of-the-art modelling suite, including hydrological and waste load models for the catchment area and a three-dimensional hydrodynamic and water quality model (Delft3D) linked to a habitat evaluation module for the lake . In addition, MS Office based tools to support a stakeholder analysis and financial and economic assessments have been developed . The project also focused on technical studies relating to dredging, drinking water supply and infrastructure works . These aimed to produce technically and economically feasible solutions to water quantity and quality problems . The paper also presents the findings of a study on the development of polder islands in the Laguna de Bay, addressing the water quantity and quality problems and focusing on the application of the decision support system.

Mar Pollut Bull, 2003, 47(1-6), 126 - 31
Recovery of fish stocks in the Seto Inland Sea; Nagai T; The total amount of fisheries' yield in the Seto Inland Sea in 1999 was 571,000 MT, consisting of 256,000 MT by fishing and 315,000 MT from aquaculture . About 40,000 people engaged in the fishing and aquaculture industries, earned 129 billion yen (1100 million US$) by fishing and 89 billion yen (770 million $US) by aquaculture . The averaged annual catch for the Seto Inland Sea by fishing was 13 MT/km(2) . Division into time periods in terms of eutrophication levels can be made: before 1960 when red sea bream were abundant with ecological divergence (before eutrophication), from 1960 to 1990 when the biomass of anchovy was large (during eutrophication), and after 1990 when the jellyfishes were abundant (excessive eutrophication or high N:P ratio) . The fish production will decrease in the sea of jellyfishes . Actually, the amount of catch was 462,000 MT in 1982 which decreased 265,000 MT in 1993, corresponding to 43% in twelve years, then keeping the same level . A big reduction was seen in the catches of the spotlined sardine, anchovy, Spanish mackerel, tiger puffer, short-necked clam, sea cucumber and others . The tiger puffer and Spanish mackerel were abundant as predators in the sea of anchovy . The biomass of anchovy was at its maximum in 1986 and decreased to less than one third in 1996 . The stocks of tiger puffer and Spanish mackerel greatly decreased because of the higher fishing pressure compared to the anchovy stock . The fishing power of individual fisheries targeting on the tiger puffer and Spanish mackerel increased substantially when fishing vessel and fishing gear improved, resulting in an excessive fishing effort . A large quantity of small immature fishes is usually caught in the Seto Inland Sea, resulting in growth and/or recruitment overfishing for many species . Hence, it is necessary to promote management of the fisheries so as not to reduce the fish stocks, and to allow the Seto Inland Sea to return from being a sea of jellyfishes to a sea of anchovy, with decreased eutrophication levels.

Mar Pollut Bull, 2003, 47(1-6), 118 - 25
Effects of deposit feeder Stichopus japonicus on algal bloom and organic matter contents of bottom sediments of the enclosed sea; Michio K et al.; Algae growing in an enclosed sea may inhibit eutrophication because they absorb nutrients in the water . However, dead algae often cause anaerobic conditions in the water just above and on sediment after they are deposited on the bottom . We found that Stichopus japonicus inhibited the anaerobic processes coupling water sulfite production in sediment . The present study investigates whether S . japonicus inhibits algal flourish and influences sediment properties such as organic matter contents . Aquarium experiments were carried out at Komatsushima port in Tokushima Prefecture, western Japan . The aquaria used in the experiments were supplied with water directly from the adjacent sea (6 L/min), laid with sand of 10 cm depths, and lighted at 12 h intervals . Six aquaria each containing a sea cucumber from Komatsushima port and six aquaria without any were used in the experiments . Water temperature ranged between 9 and 15 degrees C during December 2000 and April 2001 . Salinity ranged between 32 per thousand and 34 per thousand . Algae began to cover the bottom of the aquaria without S . japonicus after 2 weeks, whereas no growth was evident in the aquaria containing sea cucumbers . Chlorophyll a concentration in the surface sediment of the aquaria with S . japonicus (6.1+/-3.6 microg/g, mean S.D.+/-standard deviation) was significantly lower than that without it (60+/-17 microg/g, U-test, p<0.05) . Phaeophytin concentration in the surface sediment of the aquaria with S . japonicus (0.9+/-0.09 microg/g) was also significantly lower than that without it (4.5+/-1.0 microg/g, U-test, p<0.05) . TOC concentration in the surface sediment of the aquaria with S . japonicus (2.6+/-1.3 microg/g) was slightly lower than that without it (4.0+/-1.2 microg/g) . These results showed that algal biomass and organic matter concentration of the bottom were decreased in the presence of S . japonicus . Therefore, S . japonicus inhibits algal bloom and decrease the contents of organic matter deposited on the bottom of enclosed sea areas.

Mar Pollut Bull, 2003, 47(1-6), 37 - 42
The Seto Inland Sea--eutrophic or oligotrophic?
Yamamoto T.
The present water quality conditions in the Seto Inland Sea of Japan are described along with an historical background before and after the measures taken to reduce eutrophication . The directive to reduce phosphorus discharge into this area was very effective, reducing the number of red tides from about 300 cases per year at their peak in 1976 to the recent level of about 100 cases per year, indicating the improvement of seawater quality . However, the hastiness of the measures taken to reduce phosphorous seems to have led to a depletion of dissolved inorganic phosphorus that is an essential nutrient for the growth of phytoplankton . Fishery production has also decreased with the reduction of phosphorus, showing a time lag, and the relationship between them shows a hysteresis-like pattern indicating that the condition of fishery production is currently in a critical stage of collapse . This implies that the phosphorus reduction could have lowered the phytoplankton primary production and also caused a detrimental effect on the fishery production . Noteworthy is the change in the phytoplankton species composition . The dominant species that form red tides have changed from non-harmful diatoms to harmful raphidophytes in the eutrophication process and then finally to harmful/toxic dinoflagellates in the oligotrophication process . This indicates that the measures to reduce phosphorus have caused a change in phytoplankton species composition, thereby altering the food web structure, suggesting that this might be the major cause of the reduction of fishery production . In conclusion, the Seto Inland Sea of Japan is apparently in an oligotrophic condition, and it could be said to be in the state of "cultural oligotrophication" caused by the hasty reduction of phosphorus loading . Dam construction, as another possible cause of the cultural oligotrophication, is also discussed, and evidence relating to the existence of numerous dams in this area is also shown . Stress is placed on the regulation of the level of nutrients and their elemental ratio in the seawater, because these factors are considered to be effective in preventing the generation of harmful algae and in sustaining the fishery production through preservation of the natural environment . A proposal is also described regarding how these factors could be controlled.

Mar Pollut Bull, 2003 Jun, 46(6), 703 - 18
Transfer of organic contaminants to the Baltic in the Odra Estuary; Kowalewska G et al.; This paper describes the transfer of organic contaminants to the sea, using PAHs (12 compounds) and PCBs (11 congeners) as examples, through a eutrophicated coastal lagoon (Szczecin Lagoon, on the Polish-German border) . The transfer of contaminants study was based on their concentration in recent sediments (0-10 cm), in relation to different environmental conditions such as temperature, salinity, turbidity, oxygen and nutrients in water, hydrological conditions, organic carbon and biomarkers (pigments and their derivatives) in sediments . Results include the data obtained between 1994 and 2000, also those on before and afterwards the great flood in July 1997, at different stations in the Lagoon and the adjacent Pomeranian Bay . The results indicated that the eutrophic estuary of the shape of lagoon acts as an effective trap for the hydrophobic organic pollutants . The abundance and taxonomy of plankton as well as detritus derived from it play an important role in bonding the studied compounds . The salinity gradient in the lagoon has a significant influence upon deposition of the pollutants from the water column to the sediments and the residence time of the compounds there depends strongly on oxic-anoxic status of the sediments and the strength of interaction with sediments resulting from polarity, the type and stability of associates formed, as well as on hydrological conditions . We conclude that eutrophication in this area prevents pollution of the sea to some extent.

Environ Sci Technol, 2003 May 15, 37(10), 2043 - 50
Assessing TMDL effectiveness using flow-adjusted concentrations: a case study of the Neuse River, North Carolina; Stow CA et al.; Integrated control of both point and nonpoint source water pollution using Total Maximum Daily Load (TMDL) assignments will be a major regulatory focus over the next decade . We propose the use of "flow-adjusted" pollutant concentrations to evaluate the effectiveness of management actions taken to meet approved TMDLs . Pollutant concentrations are usually highly correlated with streamflow, and flow is strongly weather-dependent . Thus, pollutant loads, which are calculated as pollutant concentration multiplied by streamflow, have a large weather-dependent variance component . This natural variation can be removed by calculating flow-adjusted concentrations . While such values are not a direct measure of pollutant load, they make it easier to discern changes in streamwater quality . Additionally, they are likely to be a better predictor of pollutant concentrations in the receiving waterbody . We demonstrate the use of this technique using long-term nutrient data from the Neuse River in North Carolina . The Neuse River Estuary has suffered many eutrophication symptoms, and a program to reduce nutrient loading has been in place for several years . We show that, in addition to revealing recent reductions in nutrient inputs, annual flow-adjusted riverine nutrient concentrations show a more pronounced relationship with estuarine nutrient concentrations than do annual nutrient loads . Thus, we suggest that the calculation of flow-adjusted concentrations is a useful technique to aid in assessment of TMDL implementation.

Environ Int, 2003 Aug, 29(5), 641 - 7
Analysis of microcystins in cyanobacteria blooms and surface water samples from Meiliang Bay, Taihu Lake, China; Shen PP et al.; Taihu Lake is the third largest freshwater lake in China . In recent years, the water pollution of cyanobacteria blooms has become a severe problem in this area . Microcystins (MCs) are an important group of toxic compounds mainly produced by some cyanobacteria species and have both acute and chronic hepatotoxic effects on animals and humans . This paper presents the first data on the identification and detection of MCs in both natural occurring cyanobacteria blooms and surface water samples (0-0.5 m), collected from Meiliang Bay, Taihu Lake, China . A conventional method for extraction and isolation of MCs from cyanobacteria blooms was applied . High-performance liquid chromatography (HPLC) analysis showed that the main toxic component in the cyanobacteria materials was MC-LR . The monoclonal antibody (mAb) against MC-LR produced by hybridoma technique was employed for direct competitive ELISA to detect the concentrations of MCs in bloom and water samples collected in 2001 . The results not only revealed the presence of MCs but also temporal variations of MCs levels of three sampling stations in Meiliang Bay in 1 year . It is obvious that the MC contents were relatively higher during warm months and related with the status of eutrophication . Our study indicates the threat associated with MCs in water body of Taihu Lake . To prevent the MCs potential hazard on public health in this area, some necessary measures of monitoring and control of growth of cyanobacteria are urgently needed.

Ambio, 2003 Mar, 32(2), 98 - 105
Fish status survey of Nordic lakes: effects of acidification, eutrophication and stocking activity on present fish species composition; Tammi J et al.; The status of fish populations in 3821 lakes in Norway, Sweden and Finland was assessed in 1995-1997 . The survey lakes were chosen by stratified random sampling from all (126 482) Fennoscandian lakes > or = 0.04 km2 . The water chemistry of the lakes was analyzed and information on fish status was obtained by a postal inquiry . Fish population losses were most frequent in the most highly acidified region of southern Norway and least common in eastern Fennoscandia . According to the inquiry results, the number of lost stocks of brown trout (Salmo trutta), roach (Rutilus rutilus), Arctic char (Salvelinus alpinus) and perch (Perca fluviatilis) was estimated to exceed 10000 . The number of stocks of these species potentially affected by the low alkalinity of lake water was estimated to exceed 11000 . About 3300 lakes showed high total phosphorus (> 25 microg L(-1)) and cyprinid dominance in eastern Fennoscandia, notably southwestern Finland . This survey did not reveal any extinction of fish species due to eutrophication . One-third of the lakes had been artificially stocked with at least one new species, most often brown trout, whitefish (Coregonus lavaretus s.l.), Arctic char, rainbow trout (Oncorhynchus mykiss), pike-perch (Stizostedion lucioperca), grayling (Thymallus thymallus), pike (Esox lucius), bream (Abramis brama), tench (Tinca tinca) and European minnow (Phoxinus phoxinus) . The number of artificially manipulated stocks of these species in Fennoscandian lakes was estimated to exceed 52000 . Hence, the number of fish species occurring in Nordic lakes has recently been changed more by stockings than by losses of fish species through environmental changes such as acidification.

Environ Sci Pollut Res Int, 2003, 10(2), 126 - 39
Eutrophication of freshwater and coastal marine ecosystems: a global problem; Smith VH; GOAL, SCOPE AND BACKGROUND: Humans now strongly influence almost every major aquatic ecosystem, and their activities have dramatically altered the fluxes of growth-limiting nutrients from the landscape to receiving waters . Unfortunately, these nutrient inputs have had profound negative effects upon the quality of surface waters worldwide . This review examines how eutrophication influences the biomass and species composition of algae in both freshwater and costal marine systems . MAIN FEATURES: An overview of recent advances in algae-related eutrophication research is presented . In freshwater systems, a summary is presented for lakes and reservoirs; streams and rivers; and wetlands . A brief summary is also presented for estuarine and coastal marine ecosystems . RESULTS: Eutrophication causes predictable increases in the biomass of algae in lakes and reservoirs; streams and rivers; wetlands; and coastal marine ecosystems . As in lakes, the response of suspended algae in large rivers to changes in nutrient loading may be hysteretic in some cases . The inhibitory effects of high concentrations of inorganic suspended solids on algal growth, which can be very evident in many reservoirs receiving high inputs of suspended soils, also potentially may occur in turbid rivers . Consistent and predictable eutrophication-caused increases in cyanobacterial dominance of phytoplankton have been reported worldwide for natural lakes, and similar trends are reported here both for phytoplankton in turbid reservoirs, and for suspended algae in a large river CONCLUSIONS: A remarkable unity is evident in the global response of algal biomass to nitrogen and phosphorus availability in lakes and reservoirs; wetlands; streams and rivers; and coastal marine waters . The species composition of algal communities inhabiting the water column appears to respond similarly to nutrient loading, whether in lakes, reservoirs, or rivers . As is true of freshwater ecosystems, the recent literature suggests that coastal marine ecosystems will respond positively to nutrient loading control efforts . RECOMMENDATIONS AND OUTLOOK: Our understanding of freshwater eutrophication and its effects on algal-related water quality is strong and is advancing rapidly . However, our understanding of the effects of eutrophication on estuarine and coastal marine ecosystems is much more limited, and this gap represents an important future research need . Although coastal systems can be hydrologically complex, the biomass of marine phytoplankton nonetheless appears to respond sensitively and predictably to changes in the external supplies of nitrogen and phosphorus . These responses suggest that efforts to manage nutrient inputs to the seas will result in significant improvements in coastal zone water quality . Additional new efforts should be made to develop models that quantitatively link ecosystem-level responses to nutrient loading in both freshwater and marine systems.

Environ Manage, 2003 May, 31(5), 619 - 32
Analysis of phytoplankton community structure using similarity indices: a new methodology for discriminating among eutrophication levels in coastal marine ecosystems; Arhonditsis G et al.; Nine similarity indices based on phytoplankton community structure were examined for their sensitivity to assess different levels of eutrophication . Two phytoplankton data sets, one from an open coastal system and one from a semi-enclosed gulf, associated with different nutrient dynamics and circulation patterns were used for evaluating the indices . The results have shown that similarity indices, measuring interspecific association and resemblance of phytoplankton communities between enriched areas and control sites, were effective for detecting spatial and temporal dissimilarities in coastal marine ecosystems . The structure of the oligotrophic habitat as a potential source of ambiguity for the results was discussed, whereas the validity ranges and the potential applicability of this method were deemed to be dependent on the size of the fraction of the common species among the samples, and the similarity of the classification patterns resulted from this subcategory and those extracted from the overall community data . Furthermore, the study provides a new technique based on the use of the "Box and Whisker Plot" designed to distinguish opportunistic and rare phytoplanktonic species . The similarity indices, applied solely to the dominant species abundance, were more sensitive to resolve eutrophic, mesotrophic and oligotrophic conditions . This procedure can be proposed as an effective methodology for water characterization and can also be used as a qualitative tracer for detecting renewal processes of coastal marine ecosystems.

Phytochemistry, 2003 May, 63(2), 155 - 63
Density-dependent patterns of thiamine and pigment production in the diatom Nitzschia microcephala; Pinto E et al.; In the present study we investigate how intraspecific (density-dependent) competition for nutrients by the diatom Nitzschia microcephala affects the level of oxidative stress in the algal cells as well as their production of pigments and thiamine . N . microcephala was grown in three different densities until the stationary growth phase was reached . Throughout the experiment, growth rate was negatively related to cell density . Superoxide dismutase activity, protein thiol, and diatoxanthin concentrations indicated increasing oxidative stress with increasing cell density, which was most probably caused by nutrient depletion of the medium . Pigment contents per cell (except for diatoxanthin) decreased with increasing cell density . N . microcephala was able to synthesize thiamine and its thiamine content per cell increased in concert with cell density . In comparison, the dinoflagellate Amphidinium carterae was unable to synthesize thiamine . These results suggest that cells of N . microcephala subjected to higher competition and lower growth rates have a lower carotenoid content and a higher thiamine content . If such responses would occur in nature as well, eutrophication (higher cell densities) may alter the quality of microalgae as food items for higher trophic levels not only by species shifts in the phytoplankton, but also by changes in the cellular nutritional value within species.

Huan Jing Ke Xue, 2003 Jan, 24(1), 16 - 23
{The impact of land uses on watershed runoff nitrogen discharge in hilly regions}; Yang J et al.; Nitrogen is a crucial factor in causing the eutrophication of water body . Land use has an important impact on agricultural non-point sources (NPS) nitrogen discharge . This study on quantitative relationship of runoff nitrogen discharge and land use was conducted in Meicun watershed of Xuancheng County, Anhui Province, in the subtropical low hill area, by the dynamic monitoring of stream water and nutrient discharge, integrating interpretation of aerial image and GIS analysis . The results showed that, land use significantly affect nitrogen concentration and discharge in which nitrate nitrogen was the main component . There was a significant linear relationship between nitrate and total nitrogen concentration in the given land use system . However, statistically significant relationship between ammonium and total nitrogen concentration was found only in forest-pond system . Moreover, positive linear relationship existed between different forms of nitrogen discharge . It was found that there were exponential relationship between the discharge of nitrate, ammonium and total nitrogen and the area percentages of forest, pond, paddy and village . Forest and pond had a negative impact on nitrogen discharge while the paddy and village had positive effect . At the same time, land use types had important effect on nitrogen concentration.

Ying Yong Sheng Tai Xue Bao, 2002 Dec, 13(12), 1674 - 8
A comprehensive model for assessing lake eutrophication; Cai Q et al.; The evaluation of eutrophication or trophic state of a lake is in fact a multivariate comprehensive decision-making process quantifying the qualitative problem . Therefore, we should use a comprehensive method to assess lake eutrophication . On the basis of summarizing some comprehensive methods for assessing lake eutrophication reported in China and abroad, it is pointed out that the trophic state index (TSI) should be a major method for evaluating lake eutrophication, since it could provide a continuous numerical class of lake trophic state and a rigorous foundation of quantitative studies of eutrophication mechanism . Using analytic hierarchy process (AHP) to determine the weight attributions in the selected comprehensive indices, the authors, constructed a comprehensive assessment model as: TSI = W(Chla) x TSI(Chla) + W(Sd) x TSI(Sd) + W(TP) x TSI (TP) or TSIM = W (Chla) x TSIM(Chla) + W(Sd) x TSIM(Sd) + W(TP) x SIM(TP) where W(X) were the weights for the above three parameters with value in percentage as 54.0, 29.7 and 16.3, respectively . Additionally, the relations between comprehensive evaluation and other statistical methods such as cluster analysis were briefly discussed.

Environ Pollut, 2003, 123(3), 327 - 36
Effects of acidic deposition on forest and aquatic ecosystems in New York State; Driscoll CT et al.; Acidic deposition is comprised of sulfuric and nitric acids and ammonium derived from atmospheric emissions of sulfur dioxide, nitrogen oxides, and ammonia, respectively . Acidic deposition has altered soil through depletion of labile pools of nutrient cations (i.e . calcium, magnesium), accumulation of sulfur and nitrogen, and the mobilization of elevated concentrations of inorganic monomeric aluminum to soil solutions in acid-sensitive areas . Acidic deposition leaches essential calcium from needles of red spruce, making this species more susceptible to freezing injury . Mortality among sugar maples appears to result from deficiencies of nutrient cations, coupled with other stresses such as insect defoliation or drought . Acidic deposition has impaired surface water quality in the Adirondack and Catskill regions of New York by lowering pH levels, decreasing acid-neutralizing capacity, and increasing aluminum concentrations . Acidification has reduced the diversity and abundance of aquatic species in lakes and streams . There are also linkages between acidic deposition and fish mercury contamination and eutrophication of estuaries.

Tree Physiol, 2000 Jan, 20(1), 13 - 22
Spatial and temporal variability of foliar mineral concentration in beech (Fagus sylvatica) stands in northeastern France; Duquesnay A et al.; Foliar mineral concentration may provide a basis for monitoring the consequences of long-term environmental changes, such as eutrophication and acidification of soils, or increase in atmospheric CO(2) concentration . However, analytical drifts and inter-tree and year-to-year variations may confound environmental effects on long-term changes in foliar mineral concentration . We have characterized the relative effects of these potentially confounding factors on foliar carbon, nitrogen, phosphorus, calcium, potassium, magnesium and manganese concentrations in 118 pure beech (Fagus sylvatica L.) stands, sampled in 1969-71 and 1996-97 . Interannual fluctuations of these elements were quantified in a subset of six beech stands monitored for 5 years . Intercalibration between the methods used at each sampling period for nitrogen and phosphorus analyses showed significant, but low, relative differences (0.8 and 3.3% for N and P, respectively) . Based on inter-tree variability, elements could be arranged in four groups: C (constant), N and P (low variability), K and Ca (medium variability), Mn and Mg (high variability) . Inter-tree coefficients of variation were 2, 6, 8, 15, 18, 22 and 27%, respectively . Year-to-year fluctuations increased in the order N, P, Mg, K, Ca, and Mn coefficients of variation of 4, 4, 7, 9, 11, 15 and 29%, respectively) . Between the two sampling periods, foliar N concentration increased 12%, whereas decreases were observed for P (-23%), Mg (-38%) and Ca (-16%) . Ratios of N/P, N/K and N/Mg increased by 42, 19 and 77%, respectively . These changes were larger than the interannual variations for P, Mg, N/P, N/Mg and Mg/Ca . Decreasing concentrations of P and cations were particularly marked for trees growing on acidic soils, whereas the positive N trend did not depend on soil type . Both increasing atmospheric CO(2) concentrations and acidification of forest soils could contribute to decreasing P and cation concentrations in foliage . The increase in foliar N concentration with time suggests a nitrogen deposition effect . Whatever the causes of these changes, the large shift in element ratios indicates an accelerating imbalance between nitrogen and cation status.

Environ Monit Assess, 2003 Jan-Feb, 81(1-3), 361 - 71
Initial results from a multi-institutional collaboration to monitor harmful algal blooms in South Carolina; Lewitus AJ et al.; The rapid rate of development in the South Carolina (SC) coastal zone has heightened public concern for the condition of the state's estuaries, and alerted scientists to the potential that novel and adverse effects on estuarine ecosystems may result . Although well-developed databases from long-term monitoring programs exist for many variables valuable in predicting and following system responses, information on phytoplankton distributions in SC estuaries has lagged . Knowledge of the dynamical relationship between environmental (e.g., nutrient quantity and quality) and biological (e.g., grazing) regulation, and phytoplankton biomass and composition is critical to understanding estuarine susceptibility to eutrophication or harmful algal blooms (HABs) . Recently, SC scientists from federal, state, and academic institutions established a collaborative monitoring program to assess HAB distribution and ecology statewide . The South Carolina Harmful Algal Bloom Program includes: a) intensive temporal monitoring at areas of known HAB occurrence or those exhibiting symptoms potentially related to HABs (e.g., prevalent fish lesions), b) extensive spatial monitoring in coordination with existing statewide efforts, c) a citizen volunteer monitoring network, d) nutrient response bioassays, and e) laboratory-based physiological experiments on HAB isolates . By combining "trip-wire" surveillance and rapid response systems, routine monitoring of environmental parameters and HAB distribution, and process-oriented studies examining the physiological functioning of HAB species, an enhanced understanding of the impact and environmental control of HABs in SC estuaries will be achieved . The application of this approach to studies on the distribution and physiological ecology of a new widespread SC red tide, and to the discovery of several potentially toxic blooms (including Pfiesteria) in SC holding ponds, are described.

Environ Int, 2003 Apr, 29(1), 95 - 103
Simulation of pollution buffering capacity of wetlands fringing the Lake Victoria; Mwanuzi F et al.; Lake Victoria has undergone substantial and most negative changes, especially over the last 30 years . One of the driving factors is nutrient enrichment from human activities in the catchment, which is causing eutrophication . This has been associated with, among others, the rapid proliferation of water hyacinth, alga blooms, and with general disruption of the lake ecosystem . Most of pollution to the lake flow via the natural wetlands . In order to understand how wetlands function within the Lake Victoria ecosystem a wetland model has been developed . The main objective of the model is to establish and simulate the buffering processes and capacity of individual wetlands (that is, their ability to absorb sediments, nutrients and pollutants) within the Lake Victoria basin . It was found that in both seasonal and permanent swamp there is a net export of organic matter produced in the wetlands . Most of the inorganic phosphorous were retained in the wetlands (60% to 90% removal) while there was a negative retention of nitrates probably due to the export of organic matter which associate very much with nitrates .

Mar Pollut Bull, 2003 Mar, 46(3), 301 - 4
Viruses and marine pollution; Danovaro R et al.; This short review summarises the present knowledge on pollutant impacts on marine viruses, virus-host systems and their potential ecological implications . Excess nutrients from sewage and river effluents are a primary cause of marine eutrophication and mucilage formation, often related to the development of large viral assemblages . At the same time, hydrocarbons, polychlorinated biphenyl and pesticides alter ecosystem functioning and can determinate changes in the virus-host interactions, thus increasing the potential of viral infection . All these pollutants might have synergistic effects on the virus-host system and are able to induce prophage, thus increasing the impact of viruses on marine ecosystems.

J Environ Biol, 2002 Jul, 23(3), 239 - 46
Use of epilithic diatoms to evaluate water quality in the Karasu River of Turkey; Gurbuz H et al.; Epilithic diatom assemblages were used to evaluate water quality in the Karasu River basin (Turkey), which was polluted by industrial, agricultural and urban wastes . A total of 73 diatom taxa belonging to 22 genera were found from all seven sampling stations located in the River basin . The most pollution tolerant species Gomphonema parvulum, Nitzchia palea, Navicula cryptocephala were found in high densities at the polluted stations . Organic load (COD), biological oxygen demand in 5 days (BOD5) and concentrations of nutrients NO3(-)-N, NO2(-)-N, NH4(+)-N and PO4(3-)-P) were correlated negatively with dissolved oxygen . Except for generic index of diatoms (GI), all diatom indices were correlated significantly with COD, BOD5 dissolved oxygen and concentrations of nutrients . Saprobity index (SI), trophic diatom index (TDI) and the percentage pollution tolerant valves values suggested that the stations III, IV located in the River basin were eutrophicated and organically polluted.

Ambio, 2002 Dec, 31(7-8), 588 - 96
Seagrass ecosystems in the Western Indian Ocean; Gullstrom M et al.; Seagrasses are marine angiosperms widely distributed in both tropical and temperate coastal waters creating one of the most productive aquatic ecosystems on earth . In the Western Indian Ocean (WIO) region, with its 13 reported seagrass species, these ecosystems cover wide areas of near-shore soft bottoms through the 12 000 km coastline . Seagrass beds are found intertidally as well as subtidally, sometimes down to about 40 m, and do often occur in close connection to coral reefs and mangroves . Due to the high primary production and a complex habitat structure, seagrass beds support a variety of benthic, demersal and pelagic organisms . Many fish and shellfish species, including those of commercial interest, are attracted to seagrass habitats for foraging and shelter, especially during their juvenile life stages . Examples of abundant and widespread fish species associated to seagrass beds in the WIO belong to the families Apogonidae, Blenniidae, Centriscidae, Gerreidae, Gobiidae, Labridae, Lethrinidae Lutjanidae, Monacanthidae, Scaridae, Scorpaenidae, Siganidae, Syngnathidae and Teraponidae . Consequently, seagrass ecosystems in the WIO are valuable resources for fisheries at both local and regional scales . Still, seagrass research in the WIO is scarce compared to other regions and it is mainly focusing on botanic diversity and ecology . This article reviews the research status of seagrass beds in the WIO with particular emphasis on fish and fisheries . Most research on this topic has been conducted along the East African coast, i.e . in Kenya, Tanzania, Mozambique and eastern South Africa, while less research was carried out in Somalia and the Island States of the WIO (Seychelles, Comoros, Reunion (France), Mauritius and Madagascar) . Published papers on seagrass fish ecology in the region are few and mainly descriptive . Hence, there is a need of more scientific knowledge in the form of describing patterns and processes through both field and experimental work . Quantitative seagrass fish community studies in the WIO such as the case study presented in this paper are negligible, but necessitated for the perspective of fisheries management . It is also highlighted that the pressure on seagrass beds in the region is increasing due to growing coastal populations and human disturbance from e.g . pollution, eutrophication, sedimentation, fishing activities and collection of invertebrates, and its effect are little understood . Thus, there is a demand for more research that will generate information useful for sustainable management of seagrass ecosystems in the WIO.

J Environ Qual, 2003 Jan-Feb, 32(1), 344 - 62
Decadal change in vegetation and soil phosphorus pattern across the Everglades landscape; Childers DL et al.; Wetlands respond to nutrient enrichment with characteristic increases in soil nutrients and shifts in plant community composition . These responses to eutrophication tend to be more rapid and longer lasting in oligotrophic systems . In this study, we documented changes associated with water quality from 1989 to 1999 in oligotrophic Everglades wetlands . We accomplished this by resampling soils and macrophytes along four transects in 1999 that were originally sampled in 1989 . In addition to documenting soil phosphorus (P) levels and decadal changes in plant species composition at the same sites, we report macrophyte tissue nutrient and biomass data from 1999 for future temporal comparisons . Water quality improved throughout much of the Everglades in the 1990s . In spite of this improvement, though, we found that water quality impacts worsened during this time in areas of the northern Everglades (western Loxahatchee National Wildlife Refuge {NWR} and Water Conservation Area {WCA} 2A) . Zones of high soil P (exceeding 700 mg P kg(-1) dry wt . soil) increased to more than 1 km from the western margin canal into the Loxahatchee NWR and more than 4 km from northern boundary canal into WCA-2A . This doubling of the high soil P zones since 1989 was paralleled with an expansion of cattail (Typha spp.)-dominated marsh in both regions . Macrophyte species richness declined in both areas from 1989 to 1999 (27% in the Loxahatchee NWR and 33% in WCA-2A) . In contrast, areas well south of the Everglades Agricultural Area, induding WCA-3A and Everglades National Park (ENP), did not decline during this time . We found no significant decadal change in plant community patterns from 1989 and 1999 along transects in southern WCA-3A or Shark River Slough (ENP) . Our 1999 sampling also included a new transect in Taylor Slough (ENP), which will allow change analysis here in the future . Regular sampling of these transects, to verify decadal-scale environmental impacts or improvements, will continue to be an important tool for long-term management and restoration of the Everglades.

J Environ Qual, 2003 Jan-Feb, 32(1), 335 - 43
Spatial analysis of phosphorus sorption capacity in a semiarid altered wetland; Litaor MI et al.; The observed increase in phosphorus (P) loading into the Jordan River could increase eutrophication processes in Lake Kinneret, the only freshwater lake in Israel, which provides 25% of the country's drinking water . The P may originate from the peat soils of the highly altered Hula Valley's semiarid wetland ecosystem through which the Jordan River runs . The objectives of this research were to ascertain the sorption capacity of these soils and to identify areas with high potential for P release from soils to ground water . We extracted 80 soil samples collected across the valley with ammonium oxalate and determined the ratio of extractable P to Fe and Al, from which we derived the degree of phosphorus saturation (DPS) . A relatively low DPS (<15%) was observed in Histosols compared with the high DPS (>30%) observed in many of the hydromorphic organo-mineral soils . We used a sequential Gaussian simulation technique to assess the spatial pattern of the DPS and found that the Histosols have a low probability (<10%) of exceeding the widely used environmental DPS threshold of 25% . The areas characterized by mineral soils, such as hydromorphic Vertisols and various marl redoximorphic soils, have a high probability (>60%) of exceeding the threshold value . The ability to predict the concentrations of dissolved P in ground water based on DPS values was somewhat impaired because of the preferential flow characteristics in this altered wetland.

J Environ Qual, 2003 Jan-Feb, 32(1), 310 - 6
Relationships between phosphorus levels in soil and in runoff from corn production systems; Andraski TW et al.; Phosphorus-enriched runoff from cropland can hasten eutrophication of surface waters . A soil P level exceeding crop needs due to long-term fertilizer and/or manure applications is one of several potential sources of increased P losses in runoff from agricultural systems . Field experiments were conducted at locations representative of three major soil regions in Wisconsin in corn (Zea mays L.) production systems to determine the effect of tillage, recent manure additions, soil P extraction method, and soil sampling depth (0-2, 0-5, and 0-15 cm) on the relationship between soil test P level and P concentrations in runoff . Runoff from simulated rainfall (75 mm h(-1)) was collected from 0.83-m2 areas for 1 h after rainfall initiation and analyzed for dissolved phosphorus (DP), total phosphorus (TP), and sediment . The DP fraction of the TP concentration in runoff ranged from 5 to 17% among sites with most of the variation in TP due to varying sediment concentration on the well-drained silt loam soils and to soil test P level on the poorly drained silty clay loam soil . In 213 observations across a range of soils and managements, good relationships occurred between soil test P level and DP concentration in runoff for most of the tests and sampling depths used . Recent manure additions and high levels of surface cover from corn residue sometimes masked this relationship . The slope of DP relative to soil test P level was markedly higher on the silty clay loam soil than on the silt loam soils possibly due to soil permeability-infiltration rate differences . Agronomic soil P tests were as effective as environmentally oriented soil P tests for predicting DP concentrations in runoff.

Environ Pollut, 2003, 122(1), 19 - 28
Phosphate-induced metal immobilization in a contaminated site; Cao RX et al.; To assess the efficiency of P-induced metal immobilization in soils, a pilot-scale field experiment was conducted at a metal contaminated site located in central Florida . Phosphate was applied at a P/Pb molar ratio of 4.0 with three treatments: 100% of P from H3PO4, 50% of P from H3PO4+ 50% of P from Ca(H2PO4)2, and 50% of P from H3PO4+5% phosphate rock in the soil . Approximately 1 year after P application, soil and plant samples were collected to determine mobility and bioavailability of selected metals (Pb, Zn, and Cu) using sequential extraction procedure and mineralogical characterization using X-ray diffraction (XRD) and scanning electron microscope-energy dispersive X-ray (SEM-EDX) analysis . Phosphorus distribution and soil pH effects were also evaluated . Phosphate was more effective in transforming soil Pb (to 53%) from the non-residual to the residual phase than soil Zn (to 15%) and soil Cu (to 13%) . This was because Pb was immobilized by P via formation of an insoluble pyromorphite-like mineral in the surface and subsurface of the soil, whereas no phosphate mineral Zn or Cu was identified . While P amendment enhanced metal uptake in the roots of St . Augustine grass (Stenotaphrum secundatum), it significantly reduced metal translocation from root to shoot, especially Pb via formation of a pyromorphite-like mineral on the membrane surface of the root . A mixture of H3PO4 and phosphate rock was effective in metal immobilization, with less soil pH reduction and less soluble P . Although H3PO4 was effective in immobilizing Pb, its use should be limited to minimize soil pH reduction and potential eutrophication risk.

Mar Pollut Bull, 2002 Nov, 44(11), 1253 - 8
Deterioration of eelgrass, Zostera marina L., meadows by water pollution in Seto Inland Sea, Japan; Tamaki H et al.; Survival of transplanted Zostera marina L . (eelgrass) and environmental conditions (water quality, bottom sediments, sedimentation on leaves and flow regime) were studied concurrently in the center, edge, and at the outside of a eelgrass meadow located in a eutrophic coastal zone in northern Hiroshima Bay, Seto Inland Sea, Japan . Eelgrass transplants at the outside of the meadow declined significantly, whereas those at the center were consistently well established . Silt content in the bottom sediments at the outside was higher than that at the center . The sediment was oxic from the surface to 2 cm deep at the center, whereas those at the edge and the outside were reductive almost from the surface . The sediment characteristics typical in eutrophic water seemed to be a factor responsible for the deterioration of eelgrass meadows . Although suspended solid concentrations in the water columns were almost the same, the amount of sediments deposited on leaves of eelgrass at the outside was higher than that at the center of the meadow . The amount of the deposition at the outside seems to be enough to inhibit photosynthesis; i.e . photosynthetic photon flux density (PPFD) available for eelgrass was only 36% of that without any deposition . The deposition in the center, however, was small enough to allow 84% of the original PPFD . Flow rates, determined at 30 cm above the bottom, a half height of average eelgrass, suggested that the rate at the outside was not enough to remove deposited sediments from the surface of eelgrass leaves . Thus, the large amount of sediment deposition caused by water pollution and/or eutrophication seemed to be another factor to inhibit the survival of eelgrass at the outside edge of the meadow.

Environ Sci Technol, 2002 Dec 1, 36(23), 5075 - 82
Biogenic phosphate minerals in manure: implications for phosphorus loss to surface waters; Cooperband LR et al.; Phosphorus (P) is present in waterways throughout the United States at concentrations that impair water quality . Agriculture, particularly livestock production, has been identified as a major cause of this impairment Excess manure P applied to croplands has increased P losses in runoff, leading to surface water eutrophication . We conducted a long-term (36-week) incubation with poultry and dairy manures applied to a silt loam soil to elucidate mechanisms controlling manure P loss to water . Manures were applied to supply the same total P rate to soils with different antecedent plant-available P concentrations (soil test P) . There was a strong synergistic effect between dairy manure and soil test P on water extractable P, while soil test P did not affect P loss from poultry manure-amended soils . Using scanning electron microscopy and energy dispersive X-ray spectroscopy, we found that poultry manure contained sparingly soluble calcium and magnesium phosphate minerals that controlled soil solution P concentrations, while dairy manure did not These minerals resemble other biogenic phosphate minerals . Our findings refute current assumptions that all manure P behaves similarly in soils and that organic forms control manure-soil P loss to water.

Environ Sci Technol, 2002 Dec 15, 36(24), 5315 - 20
Hypoxia in the Baltic Sea and basin-scale changes in phosphorus biogeochemistry; Conley DJ et al.; Deep-water oxygen concentrations in the Baltic Sea are influenced by eutrophication, but also by saltwater inflows from the North Sea . In the last two decades, only two major inflows have been recorded and the lack of major inflows is believed to have resulted in a long-term stagnation of the deepest bottom water . Analyzing data from 1970 to 2000 at the basin scale, we show that the estimated volume of water with oxygen, <2 mL L(-1), was actually at a minimum at the end of the longest so-called stagnation period on record . We also show that annual changes in dissolved inorganic phosphate water pools were positively correlated to the area of bottom covered by hypoxic water, but not to changes in total phosphorus load, thus addressing the legacy of eutrophication on a basinwide scale . The variations in phosphorus pools that have occurred during the past decades do not reflect any human action to reduce inputs . The long residence time and internally controlled variation of the large P pool in the Baltic Sea has important implications for management of both N and P inputs into this eutrophicated enclosed basin.

Mar Environ Res, 2003 May, 55(4), 313 - 33
The influence of fish cage aquaculture on pelagic carbon flow and water chemistry in tidally dominated mangrove estuaries of peninsular Malaysia; Alongi DM et al.; The impact of floating net cages culturing the seabass, Lates calcarifer, on planktonic processes and water chemistry in two heavily used mangrove estuaries in Malaysia was examined . Concentrations of dissolved inorganic and particulate nutrients were usually greater in cage vs . adjacent (approximately 100 m) non-cage waters, although most variability in water-column chemistry related to water depth and tides . There were few consistent differences in plankton abundance, production or respiration between cage and non-cage sites . Rates of primary production were low compared with rates of pelagic mineralization reflecting high suspended loads coupled with large inputs of organic matter from mangrove forests, fishing villages, fish cages, pig farms and other industries within the catchment . Our preliminary sampling did not reveal any large-scale eutrophication due to the cages . A crude estimate of the contribution of fish cage inputs to the estuaries shows that fish cages contribute only approximately 2% of C but greater percentages of N (32-36%) and P (83-99%) to these waters relative to phytoplankton and mangrove inputs . Isolating and detecting impacts of cage culture in such heavily used waterways--a situation typical of most mangrove estuaries in Southeast Asia--are constrained by a background of large, highly variable fluxes of organic material derived from extensive mangrove forests and other human activities .

Water Res, 2003 Jan, 37(2), 416 - 28
Eutrophication research of West Lake, Hangzhou, China: modeling under uncertainty; Hongping P et al.; The models such as the eutrophication ecosystem model of West Lake, Hangzhou (EEM), are always used to make policy decisions for eutrophication management . Thus it is important to know the uncertainty in the model predictions due to the combined effects of uncertainty in the full set of input variables, and the individual input parameters whose variations have the greatest effect on variations in model predictions . In this study, randomized methods based on Monte Carlo technique have been developed and applied to the model (EEM) . The technique consists of parameter sensitivity analysis, randomly sampling from underlying probability distributions and multivariate regression analysis . With this technique, model uncertainties during modeling are clarified and their propagation evaluated . Results show that among the five input parameters selected for uncertainty analysis, the settling rate of algae SVS and water temperature TEM have the largest contribution to model prediction uncertainty of the model outputs (PC, PS and PHYT).

J Environ Qual, 2002 Nov-Dec, 31(6), 1918 - 29
Estimating runoff phosphorus losses from calcareous soils in the Minnesota River basin; Fang F et al.; Bioavailable phosphorus (BAP) in stormwater runoff is a key issue for control of eutrophication in agriculturally impacted watersheds . Laboratory experiments were conducted in soil runoff boxes to determine BAP content in simulated storm runoff in 10 (mostly) calcareous soils from the Minnesota River basin in southern Minnesota . The soluble reactive phosphorus (SRP) portion of the runoff BAP was significantly correlated with soil Mehlich-III P, Olsen P, and water-extractable P (all r2 > 0.90 and p < 0.001) . A linear relationship (r2 = 0.88, p < 0.001) also was obtained between SRP in runoff and the phosphorus saturation index based on sorptivity (PSIs) calculated with sorptivity as a measure of the inherent soil P sorption capacity . Runoff levels of BAP estimated with iron oxide-impregnated paper were predicted well by various soil test P methods and the PSI, of the soils, but correlation coefficients between these variables and runoff BAP were generally lower than those for runoff SRP . Using these relationships and critical BAP levels for stream eutrophication, we found corresponding critical levels of soil Mehlich-III P and Olsen P (which should not be exceeded) to be 65 to 85 and 40 to 55 mg kg(-1), respectively.

Sci Total Environ, 2002 Oct 21, 298(1-3), 81 - 102
Dinoflagellate cyst records and human disturbance in two neighboring estuaries, New Bedford Harbor and Apponagansett Bay, Massachusetts (USA); Pospelova V et al.; The dinoflagellate cyst records in sediments from New Bedford Harbor and Apponagansett Bay demonstrate sensitivity to environmental change caused by human activity in the watersheds over the last 500 years . Changes in the species richness, as well as absolute and relative abundance of dinoflagellate cyst taxa reflect recent periods of development around the estuaries . Cyst taxa sensitive to these changes include Dubridinium spp., Polykrikos schwartzii, Lingulodinium machaerophorum, Operculodinium israelianum and Selenopemphix quanta . The greatest changes in the dinoflagellate cyst record occur during the 20th century, when New Bedford Harbor was exposed to both toxic pollution and heavy nutrient loading from point and non-point sources . Apponagansett Bay was not subject to industrial pollution and nutrient enrichment has been lower (from non-point sources) . In Apponagansett Bay there is an increase in the dinoflagellate cyst species richness while species richness first increased, then declined in New Bedford Harbor . During the same period, the total dinoflagellate cyst concentration in New Bedford Harbor fluctuated over a wide range . The decline of species richness and the large fluctuations in the total cyst abundances signal the intensified anthropogenic disturbance in the watershed, notably a high degree of eutrophication and toxic pollution.

Water Sci Technol, 2002, 46(8), 19 - 28
Application of eutrophication indices for assessment of the Bulgarian Black Sea coastal ecosystem ecological quality; Moncheva S et al.; The present paper is an attempt to test the applicability of the trophic state index (TRIX) for scaling the eutrophication along the Bulgarian Black Sea coastal zone in concert with a number of chemical and biological descriptors aimed at selection of relevant indicators of marine coastal area ecological quality . The following environmental parameters have been considered: t(o), salinity, nutrients--inorganic P, N and dissolved Si, dissolved oxygen and oxygen saturation, phytoplankton--taxonomic structure, abundance and biomass, chlorophyll a, zooplankton--taxonomic structure, abundance and biomass . Principal Component Analysis was applied in order to figure out and score the most relevant combination of parameters to discriminate between sites and select representative descriptors (pressure/state) of eutrophication . The following variables are defined as relevant descriptors for classification of the sites: nutrients (N, P, Si) and their molar ratios (N:P and Si:P), the capacity of the system to produce and sustain organic matter (chlorophyll a, phytoplankton biomass), phytoplankton taxonomic dominance (Bacilariophyceae:Dinophyceae biomass ratio), grazing pressure (phytoplankton:zooplankton biomass, Bacilariophyceae:Copepoda), plankton diversity index (Hb and Ha) and the trophic state index (TRIX) . The investigated sites under a different anthropogenic impact are classified according to selected descriptors and their water quality state.

Mar Pollut Bull, 2002, 45(1-12), 300 - 10
Two-layered, 2D unsteady eutrophication model in boundary-fitted coordinate system; Chau KW et al.; The decline of water quality in Tolo Harbour in recent years is an example of eutrophication . This paper delineates a robust unsteady two-layered, 2D finite difference numerical model for eutrophication in coastal waters . The modelling is based upon the numerically generated boundary-fitted orthogonal curvilinear grid system and integrated with a hydrodynamic model . It simulates the transport and transformation of nine water quality constituents associated with eutrophication in the waters, i.e . three organic parameters (carbon, nitrogen and phosphorus), four inorganic parameters (dissolved oxygen, ammonia, nitrite + nitrate and orthophosphate), and two biological constituents (phytoplankton and zooplankton) . Key kinetic coefficients are calibrated with the field data . The hydrodynamic, pollution source and solar radiation data in the model are real-time simulated . The computational results show that the present model mimic the stratification tendency for eutrophication phenomena during summer time in the Tolo Harbour successfully . The model running time for the long-term simulation is not excessive and it can be run on a microcomputer.

Mar Pollut Bull, 2002, 45(1-12), 280 - 5
Simulation of eutrophication and associated occurrence of hypoxic and anoxic condition in a coastal bay in Japan; Karim MR et al.; A probabilistic method of calculating the occurrence of oxygen-depleted water within a combined hydrothermal and water quality model was presented in this paper to investigate the environmental impact of eutrophication on the living resources . The method was applied to an eutrophicated shallow coastal bay in western Japan, where the occurrence of red tides at the water surface and the onset of bottom hypoxic waters are observed every summer . Both meteorology and freshwater inflow contribute to the development of stratification of the bay, thus limiting the dissolved oxygen supply to bottom waters . The resulting hydrodynamics enhances the development of oxygen-depleted bottom waters by transporting organic matter produced by algal blooms to the inner bay, where it decomposes and exerts high SOD . During August, about 60% of the inner bay is hypoxic for prolonged durations and as a result most of the benthic biota and fish die . The method used here is a very useful and informative way to evaluate the spatial and temporal damage and severity caused by hypoxia on living resources . Moreover, the model results agreed very well with the observed hydrodynamics, thermal structure and water quality data of the stratified bay . The model can be used for other lakes and bays where knowledge of temperature and density stratification is important for assessing water quality.

Parasitology, 2002, 124 Suppl, S119 - 35
Parasitism at the ecosystem level in the Baltic Sea; Zander CD et al.; The Baltic Sea is characterized by organisms that can tolerate brackish water . Because of the Sea's history during glacial times, its flora and fauna (and also their parasites) can be traced to marine, freshwater and genuine brackish elements beside glacial relics . Snails, planktonic copepods, benthic amphipods and isopods are important intermediate hosts of diverse helminths; in addition polychaetes, bivalves and fishes may also act as final hosts . The most important final hosts, beside fishes, were seals and birds; these were able to disperse the parasites over the whole of the Baltic . Decreasing salinity from west to east limits the distribution of many parasites . Several marine and genuine brackish water species have almost spread over the whole Baltic . Freshwater species, however, have a lower tolerance than marine species and are only rarely found in the western part . A serious problem in the Baltic is eutrophication which can lead to massive abundances of generalist parasites, in host populations as well as host individuals . The final stage of this influence can cause a general decrease of host abundance and, as a consequence, of all kinds of parasites, due to oxygen deficiency . In comparison with the species spectrum of other brackish waters in Europe, the Baltic presents some endemic parasites as well as sharing parasite species with the Mediterranean and even the Black Sea.

Indian J Environ Health, 2001 Oct, 43(4), 164 - 8
Heavy metal pollution of river Yamuna in the industrially developing state of Haryana; Kaushik A et al.; Heavy metal concentrations viz . Fe, Ni, Pb, Cd, Co, Zn in the river Yamuna flowing along the state of Haryana through Delhi have been reported selecting 16 stations covering the upstream and downstream stations for major industrial complexes of the state . While Fe, Ni and Co concentrations exceeded the maximum permissible limits prescribed for drinking all along the river, the Cd concentrations crossed the acceptable standards in Delhi downstream . The Pb concentrations declined in the eutrophicated Delhi downstream while Zn concentrations remained within desirable limits throughout . Peak concentrations were recorded in Delhi downstream for Fe and at Sonepat-Gohana downstream for Ni, Co & Zn, which matched with the type of industrial inputs viz . Iron-works and the electroplating, galvanizing & cycle industries, respectively . The status of heavy metal pollution of the river has been discussed with respect to possible impacts on human health and aquatic life.

Environ Monit Assess, 2002 Oct, 79(1), 13 - 27
A proposal for a long-term baseline phytobenthos monitoring programme for the Finnish Baltic coastal waters: monitoring submerged rocky shore vegetation; Back S et al.; Several local surveys on the submerged vegetation have been conducted in past decades along the Finnish Baltic coastal areas . Surveys have been carried out by using various methods, which make the temporal comparisons of the results difficult . The need of a joint programme for coastal phytobenthic monitoring is emphasised by the Nordic Council of Ministers and HELCOM . The Finnish coastal phytobenthic monitoring programme complements the Baltic HELCOM monitoring programme (COMBINE) . It is primarily designed to reveal the effects of eutrophication . The programme includes general principles for selection of monitoring areas as well as a proposal for monitored habitats, communities and species . The need of evaluated and tested field methods, data collecting, interpretation and data storage are addressed in the Quality Assurance part . The cost-efficiency is secured by integrating the phytobenthos programme with the coastal water monitoring for obtaining the supporting data such like salinity, temperature and nutrients . In the design of the monitoring programme a special interest is paid on areas with high protection values such as Natura 2000 or HELCOM's BSPA (Baltic Sea Protected Areas) or on aspects that would support the implementation of the EU Water Framework Directive.

J Environ Qual, 2002 Sep-Oct, 31(5), 1601 - 9
Soil testing to predict phosphorus leaching; Maguire RO et al.; Subsurface pathways can play an important role in agricultural phosphorus (P) losses that can decrease surface water quality . This study evaluated agronomic and environmental soil tests for predicting P losses in water leaching from undisturbed soils . Intact soil columns were collected for five soil types that a wide range in soil test P . The columns were leached with deionized water, the leachate analyzed for dissolved reactive phosphorus (DRP), and the soils analyzed for water-soluble phosphorus (WSP), 0.01 M CaCl2 P (CaCl2-P), iron-strip phosphorus (FeO-P), and Mehlich-1 and Mehlich-3 extractable P, Al, and Fe . The Mehlich-3 P saturation ratio (M3-PSR) was calculated as the molar ratio of Mehlich-3 extractable P/{Al + Fe} . Leachate DRP was frequently above concentrations associated with eutrophication . For the relationship between DRP in leachate and all of the soil tests used, a change point was determined, below which leachate DRP increased slowly per unit increase in soil test P, and above which leachate DRP increased rapidly . Environmental soil tests (WSP, CaCl2-P, and FeO-P) were slightly better at predicting leachate DRP than agronomic soil tests (Mehlich-1 P, Mehlich-3 P, and the M3-PSR), although the M3-PSR was as good as the environmental soil tests if two outliers were omitted . Our results support the development of Mehlich-3 P and M3-PSR categories for profitable agriculture and environmental protection; however, to most accurately characterize the risk of P loss from soil to water by leaching, soil P testing must be fully integrated with other site properties and P management practices.

Water Sci Technol, 2002, 46(4-5), 179 - 84
Effect of pH control on EBPR stability and efficiency; Serafim LS et al.; Biological phosphorus removal from water surfaces is an important process for the control of eutrophication . Even though much attention has been devoted to understanding the metabolism of bacteria and the effect of operational parameters on the efficiency of the phosphorus removal process, certain aspects are still unclear . The aim of this work was to evaluate the influence of pH control on the stability and efficiency of two sequenced batch reactors (SBR): one operated with pH control (pH 7.0) and the other without pH control (pH raised from around 7.8 to 8.5) . The reactor operated without pH control showed higher efficiency on phosphorus removal and stability than the reactor with pH control . Based on the kinetics of both reactors it could be inferred that a different population developed in both systems.

WHO Reg Publ Eur Ser, 2002, (93), III - XXIII, 1-222
Water and health in Europe . A joint report from the European Environment Agency and the WHO Regional Office for Europe; The influence of microcystin-LR and hepatotoxic cyanobacterial extract on the water plant Spirodela oligorrhiza; Department of Plant Growth Regulation, University of Lodz, Lodz, Banacha 12/16, 90-237 Lodz, Poland . romano@biol.uni.lodz.pl

The eutrophication of the Sulejow Reservoir dam in Poland is related to toxicity from cyanobacterial blooms . The main species responsible for hepatotoxic bloom formation is Microcystis aeruginosa . The aim of this study was to evaluate the influence of toxic cyanobacterial extract on the growth and morphology of the water plant Spirodela oligorrhiza, compared with commercial-grade microcystin-LR (MC-LR) . It was found that after 96 h of incubation the highest concentration of cyanobacterial extract, containing 0.344 mg MC-LR/L, reduced the number of fronds by about 50% in comparison with the control . The extract effected a reduction in the frond mass and a decrease in chlorophyll (a + b) concentration . A reduction in the number of fronds was also observed after the first 24 h of incubation in the presence of 0.2 and 0.1 microg/L of commercial-grade MC-LR . Changes in activity of constitutive acid phosphatase and RNase after 7 days of incubation with commercial-grade MC-LR were observed . The results confirm the toxicity of cyanobacterial hepatotoxins to Spirodela oligorrhiza, which can be used as a sensitive bioindicator .

Water Res, 2002 Aug, 36(14), 3593 - 601
Nutrient and grazing factors in relation to phytoplankton level in a eutrophic shallow lake: the effect of low macrophyte abundance; Lau SS et al.; The ability of submerged macrophytes to moderate the structure of food webs with respect to lake eutrophication management has been intensively studied in recent years . Many lake managers have adopted the option of increasing macrophyte abundance in order to restore eutrophic waters, with a view to improve water quality, increase water transparency and reduce phytoplankton biomass . These studies are mostly based upon the comparison of macrophyte-rich and macrophyte-free waters . There is less quantitative information on how different levels of macrophyte abundance, in particular very low levels, influence ecosystem structure, or vice versa, within the same ecosystem . This paper takes a multivariate statistical approach to examine ecosystem function with low macrophyte abundance (ca . 5%) in the context of nutrient-phytoplankton-zooplankton interaction in a eutrophic shallow lake . It shows that with low levels of macrophyte coverage, phytoplankton biomass was only limited by nutrient (TP and Si) availability, whilst nutrient (Si) as well as grazing (zooplankton and Daphnia) factors were both limiting phytoplankton levels in macrophyte-free waters . With respect to interactions between Daphnia and chlorophyll-a, the results suggest that low macrophyte cover does not result in a reduction of phytoplankton biomass due to the presence of Daphnia . Rather, low macrophyte cover provides a refuge that maintains constant Daphnia predation, so reducing chlorophyll-a fluctuation . These results add credence to the causal interpretation of different interactions amongst nutrients, phytoplankton and zooplankton at very low macrophyte densities.

Mar Pollut Bull, 2002 Jul, 44(7), 611 - 22
Assessing the trophic state and eutrophication of coastal marine systems: a new approach based on the biochemical composition of sediment organic matter; Dell'Anno A et al.; We used a biochemical approach based on the analysis of the quality and quantity of sedimentary organic matter for identifying new descriptors of the trophic state and environmental quality of coastal marine systems . A large-scale study, including 99 stations, belonging to 33 transects, was carried out along 250 km of the Apulian coasts (Mediterranean Sea) in March and September 2000 . The investigated area covered a wide range of anthropogenic impacts (industrial ports, tourist harbours, areas affected by power plants and industrial wastes, mariculture areas) . Other sites, including marine protected areas (i.e., without any apparent impact), were used as "control" . Water column and benthic parameters provided different indications and classifications of the trophic state of coastal marine systems . We found that phytopigment content of the sediments changed in response to all different sources of anthropogenic impact and resulted in a useful descriptor of the trophic state and environmental quality . Highest sediment chlorophyll-a concentrations, indicating conditions of increasing eutrophication, were found in areas impacted by the discharge of heated waters from a power plant . In particular, the contribution of the autotrophic biomass to the biopolymeric carbon pool appeared to be a good descriptor of the decreasing environmental quality . Independently from the sampling period or the pollution source such contribution was significantly lower in transects subjected to anthropogenic impact than in control areas . Differences in trophic conditions were evident both in terms of quantity (i.e., total organic matter content) and quality (i.e., biochemical composition) of sediment organic matter . In particular, sediment protein concentration appeared to be a good descriptor of the trophic state of the benthic systems at different spatial scales . Multivariate (MDS) analysis allowed identifying areas characterised by hypertrophic, eutrophic and meso-oligotrophic conditions and to define relative threshold levels . A classification of the trophic state of coastal systems based on protein and carbohydrate concentrations is proposed.

Environ Int, 2002 Jul, 28(3), 165 - 71
Variation of nutrient and metal concentrations in aquatic macrophytes along the Rio Cachoeira in Bahia (Brazil); Klump A et al.; The use of cuprous fungicides in cocoa production in the southern part of the state of Bahia (Brazil) for decades has caused an accumulation of copper in various components of the cocoa plantations, and a contamination of regional freshwater ecosystems is suspected . Urban and industrial sources are supposed to contribute to water pollution and eutrophication of the Rio Cachoeira, the main river in this region . In order to study the metal contamination and nutritional status of this freshwater ecosystem, samples of the aquatic macrophytes Eichhornia crassipes and Pistia stratiotes were collected at seven sites along the river course . The samples were analysed for their copper, aluminium, chromium, nitrogen and phosphorus concentrations . The levels of heavy metals increased in the downstream direction, particularly in the roots of water hyacinth . A dramatic increase of nitrogen and phosphorus concentrations in water as well as in plant tissues was found in samples collected downstream from the city of Itabuna . Metal input and eutrophication were attributed to agricultural, industrial and urban sources in the region . Biomonitoring of the water quality using aquatic macrophytes as accumulative indicator plants is recommended in addition to chemical water analyses.

Environ Toxicol, 2002, 17(4), 407 - 13
Possible allelopathic effects of cyanotoxins, with reference to microcystin-LR, in aquatic ecosystems; Pflugmacher S; During recent years a shift from macrophyte-dominated to more phytoplankton-dominated lakes has been correlated to the process of eutrophication . The existence of numerous substances exhibiting allelopathic effects on the growth of algae has been shown in different aquatic macrophytes (e.g., Myriophyllum spicatum) and is thought to be an important mechanism in stabilizing the macrophyte-dominated clear-water state of a lake . A few recent studies have shown that algae themselves can produce special substances inhibiting growth or photosynthetic processes in other algae . A well-known cyanobacterial secondary metabolite, microcystin-LR, was tested for its allelopathic power on aquatic macrophytes such as Ceratophyllum demersum and Myriophyllum spicatum, resulting in growth inhibition, reduction in photosynthetic oxygen production, and changes in pigment pattern . This shows that microcystin-LR has a possible role as an allelopathic infochemical .

Water Res, 2002 Jul, 36(13), 3314 - 22
Cyanobacteria-mediated internal eutrophication in shallow Lake Balaton after load reduction; Istvanovics V et al.; Nutrient loads to large, shallow Lake Balaton have been reduced by 45-50% since mid-1980s . While a delayed, but still surprisingly fast recovery was observed in the hypertrophic western areas of the lake, eutrophication followed sewage diversion from the mesotrophic northern basins . We assessed factors that could lead to this unusual response . The prime reason of the observed biomass increase might be a trend of increasing mean water temperature during late summers and the concurrent invasion of the subtropical cyanobacterium, Cylindrospermopsis raciborskii with superior light and nutrient utilisation capabilities . In the mesotrophic areas, the prerequisite of the unforeseen success of C . raciborskii was the exceptionally high potential of this species to generate internal P load . Specific morphometric features of the lake rather than nutrient loads might substantiate the increasing dominance of the cyanobacterium in these areas . Our results stress the need to consider individual characteristics of aquatic ecosystems during eutrophication management.

Braz J Biol, 2002 Feb, 62(1), 77 - 84
Diversity and biomass of chironomidae (Diptera) larvae in an impacted coastal lagoon in Rio De Janeiro, Brazil; Callisto M et al.; Diversity and biomass of Chironomidae larvae were studied between January-November 1993 and March-November 1994 in an impacted lagoon in Rio de Janeiro, Southeastern Brazil, in an attempt to establish the ecological consequences of anthropogenic eutrophication processes . Nine hundred and seventy-five organisms belonging to the Tanypodinae, Orthocladiinae, and Chironominae were collected . Polypedilum (62%) and Chironomus (58%) were the most common genera found in the limnetic and littoral zones.

Parasitol Res, 2002 Aug, 88(8), 734 - 44 Epub 2002 Apr 27.
Parasite populations and communities from the shallow littoral of the Orther Bight (Fehmarn, SW Baltic Sea); Zander CD et al.; Parasites of host guilds, such as mud snails (five species), benthic crustaceans (six species) and small-sized fishes ( Pomatoschistus microps, Gasterosteus aculeatus, Pungitius pungitius, young Pleuronectes flesus), were investigated in the Other Bight off West Fehmarn (Kiel Bight, German Baltic Sea) . The hosts, especially the herbivorous Hydrobia spp, Gammarus spp and Idothea chelipes, attained extremely high densities in three habitats ( Enteromorpha belt, Fucus belt, sandy bottom), which may be a consequence of high eutrophication . Fish as carnivores and several helminths as parasites can profit from these massive appearances - more than 5,000 Hydrobia mud snails/m(2) or 282 I . chelipes/m(2) . Prevalences of mud snails peaked in summer, by up to 30% extra, whereas species of benthic crustaceans attained increases of 47-100%, fish 57-100% . The most abundant helminths were the digeneans Maritrema subdolum, Microphallus claviformis and Asymphylodora demeli in Hydrobia spp, Maritrema subdolum, Microphallus papillorobustum, Levinseniella brachysoma and Podocotyle atomon in benthic crustaceans and Cryptocotyle concavum, Podocotyle atomon and Brachyphallus crenatus in fish . The copepod Thersitina gasterostei was also abundant in sticklebacks . The density of parasites (number/m(2)) peaked in summer, with more than 10,000 Maritrema subdolum metacercariae in I . chelipes from the Fucus belt and more than 1,000 in I . chelipes from the Enteromorpha belt or the sandy bottom . There was a clear seasonality in the appearance of digeneans in G . locusta, G . salinus and I . chelipes infected by M . subdolum and Gammarus spp infected by L . brachysoma and P . atomon . Therefore, the Orther Bight may be a epizootiotope for M . subdolum and C . concavum, i.e . a habitat with an extreme infection rate which can endanger the population of the host . Idothea chelipes also has a high infection potential to the final hosts of M . subdolum, crustacean-feeding birds . Similar relationships were found between the bird digenean C . concavum and the common goby Pomatoschistus microps . The infection mechanisms of both benthic crustaceans and small-sized fish follow the rule of predation in two steps: dispersion and accumulation.

J Agric Food Chem, 2002 Jul 17, 50(15), 4393 - 9
Potential influence of sugarcane cultivation on estuarine water quality of Louisiana's gulf coast; Southwick LM et al.; Sugarcane is cultivated on some 170000 ha of land in south central and southwestern Louisiana . This acreage drains into bayous and rivers that empty into Louisiana's coastal bays and estuaries . For a number of years the state's Department of Agriculture and Forestry and Department of Environmental Quality have collected water quality data from this sugarcane area . Study of these data shows that approximately one in five detections of atrazine is above the maximum contaminant level (MCL) for drinking water . Currently there is no U.S . atrazine standard for protection of aquatic life . February and October detections of this herbicide are probably due to sugarcane cultivation . Nitrate levels have remained below the MCL for drinking water, but nitrate and phosphorus concentrations may pose a potential for eutrophication problems . The contribution of sugarcane production to the nutrient status of Louisiana's coastal water bodies is difficult to assess because there are other sources of nutrients in the area and native soil phosphorus levels are high . Cultural practices such as subsurface drains, open drainage ditches, and postharvest residue management have potential through enhancement of soil infiltration for decreasing sugarcane's contribution to water quality problems in southern and coastal Louisiana . A new field project is being installed at the Louisiana State University Agricultural Experiment Station's Sugarcane Research Station at St . Gabriel to assess the water quality benefits of these practices with respect to sugarcane cultivation.

Water Sci Technol, 2002, 45(9), 87 - 94
Wetland management to reduce Baltic Sea eutrophication; Paludan C et al.; Seven regions with coastal eutrophication problems in the Baltic Sea, including the Kattegat, constitute the BERNET project (Baltic Eutrophication Regional Network) . To counteract eutrophication and associated severe biological conditions the countries around this large brackish water body must all cooperate . The regions are characterized by large differences in land use, e.g . agricultural intensity, and losses of retention capacity in the catchments due to wetland reclamation . Initially it has been necessary to identify nutrient sources--especially nitrogen--and technical, economical and even administrative obstacles to initiate eutrophication management measures . Nitrogen retention in different types of wetlands in the Baltic Sea Region has been analysed . The wetlands generally have a positive effect on reduced nitrogen transport to aquatic environments and it is generally accepted that measures leading to decreased losses of nutrients to the aquatic environment must be combined with measures leading to increased retention of nutrients in catchments . Data analysed in the BERNET project show that the potential for such a measure is large . Therefore, conservation and restoration initiatives for wetlands is an essential part of the work in the BERNET project . Wetlands have been drained or totally eliminated due to intensive agriculture in some regions while large scale rehabilitation of wetlands occurs in regions with less intensive agriculture . Based on land use data from the seven regions, the working group for wetland management within the BERNET project has identified the possible use of wetlands as building blocks as a contribution to the management of the Baltic Sea eutrophication . Several recommendations are presented on the wise use of existing and constructed wetlands for water quality management in relation to non-point nutrient pollution.

Water Sci Technol, 2002, 45(9), 43 - 50
Implementation of best management practices in agriculture: modelling and monitoring of impacts on nitrogen leaching; Joelsson A et al.; In Kattegat and the coastal water of the Baltic Sea, high nitrogen input from agricultural land is considered to be the main reason for eutrophication . International agreements and governmental programs have set a target to reduce the anthropogenic nitrogen load by 50 percent . Improved nitrogen removal in treatment plants and efforts in agriculture have so far not decreased nitrogen transport to a sufficient extent . In this project the impact of agricultural practices on nitrogen leaching was investigated in two small agricultural catchments in Southwest Sweden . The root-zone leaching was estimated by an indexing technique . Simultaneously the transports in the stream outlets were monitored . During 1995 and 1999 the agricultural practices in the catchments were surveyed . Field data from the first survey indicated that fertilisation did not always match crop requirements, the area of undersown catch crop can be increased and autumn cultivation can be reduced . The second survey was preceded by an advisory campaign where each farmer was visited and presented with an environmental plan including fertilisation, cultivation, and crop rotation for the farm . The plan summarised the best management practices that could be realised under actual conditions . Results from the second survey showed that some changes in the agricultural practices were carried out after the advisory campaign . The nitrogen leaching from the root-zone was then estimated by the indexing technique, both for the time before and after the advisory program . The results showed that the estimated nitrogen leaching, as a mean value for 330 fields, decreased from 53 to 50 kgN ha(-1), due to adjustments of the agricultural practices . Monitoring of stream transports showed values of the same magnitude after correction for retention and other sources . In this short time perspective, decreases in transport due to changes in agricultural practices could not be separated from influence of weather conditions . In comparison to results from the Swedish monitoring programme for agriculture, the measured transports were normal for the region, where annual variation in precipitation and runoff is large . Theoretically, nitrogen leaching could be reduced by one third without any major economic constraints for the farmers . In general, the farmers were positive to advice and willing to try new farming techniques even if some measurements were not fully implemented during the investigation period.

Ambio, 2002 Mar, 31(2), 120 - 5
Reactive nitrogen and human health: acute and long-term implications; Wolfe AH et al.; Reactive-nitrogen (Nr) has a wide variety of beneficial and detrimental effects on human health . The most important of the beneficial effects are increasing global and regional food supplies and increased nutritional quality of available foods . However, lack of adequate dietary intake of amino acids and proteins is a serious cause of malnutrition when food supplies are inadequate because of poverty, drought, floods, wars, and displacements of people as refugees . There is sufficient, though limited, quantitative data indicating that increased circulation of Nr in the environment is responsible for significant human health effects via other exposure pathways . Nr can lead to harmful health effects from airborne occupational exposures and population-wide indoor and outdoor air pollution exposures to nitrogen dioxide and ozone . Nr can also affect health via water pollution problems, including methemoglobinemia from contaminated ground water, eutrophication causing fish kills and algal blooms that can be toxic to humans, and via global warming . The environmental pollutants stemming from reactive nitrogen are ubiquitous, making it difficult to identify the extent to which Nr exerts a specific health effect . As all populations are susceptible, continued interdisciplinary investigations are needed to determine the extent and nature of the beneficial and harmful effects on human health of nitrogen-related pollutants and their derivatives.

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