Mycorrhiza, 2002 Jun, 12(3), 147 - 51 Epub 2002 Mar 27. Ectomycorrhizal root development in wet Alder carr forests in response to desiccation and eutrophication; Baar J et al.; Effects of desiccation and eutrophication on ectomycorrhizal (ECM) root development in wet Alder carr forests in The Netherlands were studied . In northwestern Europe, wet Alder carr forests are found mostly in peatlands and along streams, forming an important component of wetland ecosystems . The dominant tree species in wet Alder carr forests is Alnus glutinosa (L.) Gaertn . (Black alder), which associates with ectomycorrhizal fungi . During recent decades, wet Alder carr forests in Europe have declined because of desiccation and eutrophication, particularly in The Netherlands . In the present study, the number of root tips of A . glutinosa trees was highest in an undisturbed wet Alder carr forest in a peatland area . Eutrophication in the peatland area significantly inhibited ectomycorrhizal (ECM) root development of A . glutinosa . In the eutrophied forest, ECM root tips were observed only close to A . glutinosa trees growing on hummocks . The concentrations of nitrate and potassium in soil water of the eutrophied forest were significantly higher than in the undisturbed forest, while magnesium and iron concentrations and the pH were significantly lower . The number of ECM root tips of A . glutinosa in a desiccated forest along a stream was generally lower than in an undisturbed wet Alder carr forest on waterlogged soil in the same area . The sulphate concentration in soil water in the desiccated forest was significantly higher than in the forest on waterlogged soil . ECM root development of A . glutinosa may have been negatively affected by the chemical composition of the soil water. Braz J Biol, 2001 Nov, 61(4), 523 - 40 Epub 2002 May 24. Association of periphytic diatom species of artificial substrate in lotic environments in the Arroio Sampaio Basin, RS, Brazil: relationships with abiotic variables; Oliveira MA et al.; Associations of diatom species were identified, in the Arroio Sampaio Basin, Rio Grande do Sul, Brazil, based on monthly samplings over a year along Arroio Sampaio and its main tributaries, using polyamide thread as an artificial substrate . The species groupings showed four different environments: medium-lower course of Arroio Sampaio; and lower course of Arroio Teresinha; upper course of Arroio Sampaio; and lower course of Arroio Duvidosa . Among the physical and chemical variables measured, water pollution, particularly organic contamination and eutrophication, measured from BOD, and total phosphate concentration, respectively, appeared to be one of the most important environmental factors determining the composition and structure of species associations in the area studied. Parazitologiia, 2002 Mar-Apr, 36(2), 140 - 5 {Ectoparasite infection of some fish species in lake Pleshcheev}; Zharikova TI et al.; Ectoparasites have been investigated on gills of the ruff, perch, white bream, roach, bream, ide, and European cisco from the Pleshcheevo lake . 13 parasite species were found: Dactylogyrus falcatus, D . distinguendus, D . cornoides, D . cornu, D . sphyrna, D . robustus, D . amphibothrium, Ancyrocephalus paradoxus, Argulus foliaceus, Ergasilus sieboldi, Achtheres percarum, Ancyrocephalus percae, and Rhipidocotyle companula . A reliable negative correlation between the number of monogeneans An . paradoxus and the copepods Ac . percarum on the perch . D . falcatus, the specific monogenean of the bream, was found on the roach . The comparison of the obtained data with those of 1939 has shown the decrease of oxyphilic copepods E . seiboldi, that prove the increasing eutrophication. Environ Toxicol Chem, 2002 Jun, 21(6), 1219 - 28 Bioavailability of metals to the amphipod Monoporeia affinis: interactions with authigenic sulfides in urban brackish-water and freshwater sediments; Wiklund AK et al.; Could reduced eutrophication be a potential environmental threat because of increased mobility and bioavailability of trace metals? This question was addressed by oxygenating intact sediment cores, varying in redox potential and salinity, in a test system containing the amphipod Monoporeia affinis . Results show a low mobility of metals during oxygenation, and despite high concentrations of metals in sediments, only Pb showed a notable degree of bioaccumulation . Cadmium was bioaccumulated particularly in freshwater sediment, and body burden of Cd was related to salinity, porewater, and sediment concentrations . Despite high sediment and porewater concentrations of Cu and Zn, no relationship was recorded to body burden . For three of four tested metals, Cd, Pb, and Zn, metals in sediment were more important for body burdens in amphipods as compared to metals in porewater . Food, rather than interstitial water, therefore seems to be the main route of metal contaminants to these amphipods . Furthermore, this observed low release of metals from sediments and low body burden significance of porewater metals indicate that ameliorated oxygen conditions in contaminated sediments may be regarded as a minor environmental threat for one of the most important Baltic benthic organisms. Mar Environ Res, 2002 Jun, 53(5), 465 - 79 Reed (Phragmites australis) decline in a brackish wetland in Italy; Fogli S et al.; A comparative field study was carried out at two sites (a healthy site and a declining site) in a brackish wetland in northern Italy, with the objective to investigate the symptoms and the possible causes leading to reed (Phragmites australis) decline in this area . The declining reed plants presented many of the symptoms (clumping habit, smaller size, weaker culms, abnormal rhizome and root anatomy, low starch levels in rhizomes) comprised within the so-called reed die-back syndrome, frequently observed in central European wetlands but never recorded previously in (Sub)Mediterranean regions . Soil nutrient levels did not differ much between the two sites, with nitrate concentrations in the soil being even higher at the healthy site (1.54 microg g(-1); die-back site 0.76 microg g(-1)) . Hence, eutrophication did not seem to represent a major cause in determining reed decline in this area . High sulphate concentrations in saltwater associated with low soil redox potentials (-215 mV) due to waterlogging resulted in high soil sulphide concentrations . Concentrations of organic acids, especially acetic acid, did not differ remarkably between sites . High sulphide levels presumably accounted for abnormal anatomical formations (callus blocking aerenchyma channels), lower rates of net CO2 exchange and reduced reserve storage, observed at the die-back site . This was associated with a lower mechanical resistance of reed culms which accelerated reed mortality in the die-back areas . We concluded that high sulpihde levels in permanently waterlogged soils may result in die-back of reed stands in Mediterranean wetlands. J Environ Sci Health A Tox Hazard Subst Environ Eng, 2002, 37(5), 913 - 24 In situ experimental evidence of phosphorus limitation on algal growth in a lake ecosystem; An KG et al.; This paper presents the results of in situ Nutrient Stimulation Experiments (NSEs) demonstrating that phosphorus was the primary nutrient controlling algal growth in the Taechung Reservoir, Korea . Algal response in most treatments with only nitrogen added was less than or the same as in the controls, whereas the growth in treatments enriched with phosphorus increased by as much as fivefold . Phosphorus limitation was consistent over the experimental period when bioassay experiments were conducted, but the magnitude of growth response to phosphorus enrichments varied with the season . Algal yield in P-treatments was maximum when thermal stratification was strong and total dissolved phosphorus (TDP) was near the level of depletion . Regression analyses of NSEs showed that in situ algal response in P treatments, measured as log-transformed CHLf:CHLi ratios, declined (R2 = 0.995, p < 0.001) with ambient concentrations of log-transformed TDP . Also, algal response in the P treatments showed a first-order linear fit (R2 = 0.961, p < 0.001) with log-transformed DIN (dissolved inorganic nitrogen):TDP ratios . These outcomes indicate that the magnitude of in situ algal response increased with lower levels of P and higher dissolved N:P ratios in the ambient lake water . Our experimental approach employing NSEs suggests that abatement of phosphorus from the watershed seems to be an efficient management strategy to control the eutrophication of this system. J Environ Sci (China), 2002 Apr, 14(2), 255 - 63 History, development and characteristics of lake ecological models; Xu FL et al.; This paper provides some introductory information on the history, development, and characteristics of various lake ecosystem models . The modeling of lake ecological processes began to gain importance in the early 1960s . There are a number of models available today, with varying levels of complexity to cope with the variety of environmental problems found in lake environments, e.g . eutrophication, acidification, oxygen depletion, wetland management, heavy metal and pesticide pollution, as well as hydrodynamic problems . In particular, this paper focuses on lake eutrophication and wetland models, as well as addressing strategies appropriate for the design and development of reliable lake ecological models. Environ Sci Technol, 2002 May 15, 36(10), 2109 - 15 Predicting the frequency of water quality standard violations: a probabilistic approach for TMDL development; Borsuk ME et al.; To address the impaired condition of the water bodies listed under Section 303(d) of the Clean Water Act, over 40 000 total maximum daily loads (TMDLs) for pollutants must be developed during the next 10-15 years . Most of these will be based on the results of water quality simulation models . However, the failure of most models to incorporate residual variability and parameter uncertainty in their predictions makes them unsuitable for TMDL development . The percentile-based standards increasingly used by the EPA and the requirement for a margin of safety in TMDLs necessitate that model predictions include quantitative information on uncertainty . We describe a probabilistic approach to model-based TMDL assessment that addresses this issue and is suitable for use with any type of mathematical model . To demonstrate our approach, we employ a eutrophication model for the Neuse River Estuary, North Carolina, and evaluate compliance with the state chlorophyll a standard . Any observed variability in chlorophyll athatis notexplained bythe model is explicitly incorporated via a residual error term . This probabilistic term captures the effects of any processes that are not considered in the model and allows for direct assessment of the frequency of standard violations . Additionally, by estimating and propagating the effects of parameter uncertainty on model predictions, we are able to provide an explicit basis for choosing a TMDL that includes a margin of safety . We conclude by discussing the potential for models currently supported by the EPA to be adapted to provide the type of probabilistic information that is necessary to support TMDL decisions. Philos Trans R Soc Lond B Biol Sci, 2002 Apr 29, 357(1420), 449 - 69 Inositol phosphates in the environment; Turner BL et al.; The inositol phosphates are a group of organic phosphorus compounds found widely in the natural environment, but that represent the greatest gap in our understanding of the global phosphorus cycle . They exist as inositols in various states of phosphorylation (bound to between one and six phosphate groups) and isomeric forms (e.g . myo, D-chiro, scyllo, neo), although myo-inositol hexakisphosphate is by far the most prevalent form in nature . In terrestrial environments, inositol phosphates are principally derived from plants and accumulate in soils to become the dominant class of organic phosphorus compounds . Inositol phosphates are also present in large amounts in aquatic environments, where they may contribute to eutrophication . Despite the prevalence of inositol phosphates in the environment, their cycling, mobility and bioavailability are poorly understood . This is largely related to analytical difficulties associated with the extraction, separation and detection of inositol phosphates in environmental samples . This review summarizes the current knowledge of inositol phosphates in the environment and the analytical techniques currently available for their detection in environmental samples . Recent advances in technology, such as the development of suitable chromatographic and capillary electrophoresis separation techniques, should help to elucidate some of the more pertinent questions regarding inositol phosphates in the natural environment. Environ Pollut, 2002, 118(3), 351 - 5 Tolerance to, and avoidance of, hypoxia by the penaeid shrimp (Metapenaeus ensis); Wu RS et al.; Aquatic hypoxia caused by eutrophication may lead to mass mortality of valuable living resources such as fish and shrimp . However, there is little information on the hypoxic tolerance of penaeid shrimp, and whether they are able to avoid hypoxia . In laboratory experiments, LC50, LT50 and heart beats per minute were determined for juvenile Metapenaeus ensis at 0.5, 1.0, 2.0 and 6.0 mg O2 l(-1) . The 8-h LC50, for DO was 0.77 mg O2 l(-1), while the LT50 at 0.5 mg O2 l(-1) was 399 min . Heart beat rate significantly declined when DO fell below 1.0 mg O2 l(-1) . When confronted with a gradient of dissolved oxygen, M . ensis were able to avoid hypoxic areas and move to oxygenated water . M . ensis appeared to be sensitive to hypoxia, and their ability to detect and avoid hypoxia may enhance their survival in habitats where hypoxia may occur. J Environ Manage, 2002 Feb, 64(2), 99 - 113 Geographic information system based manure application plan; Basnet BB et al.; A geographic information system (GIS) based manure application plan has been developed for the site-specific application of animal waste to agricultural fields in the Westbrook sub-catchment of the Murray-Darling Basin, south-east Queensland, Australia . Sites suitable for animal waste application were identified using a GIS based weighted linear combination (WLC) model . The degree of land suitability for animal waste application was determined using a range of social, economic, environmental, and agricultural factors . As eutrophication and toxic blue-green algae blooms are a known problem in the catchment, the manure application rates were limited to the rate of crop phosphorus removal . Maximum manure application rate was calculated spatially by taking the crop nutrient (P2O5) requirement and the manure nutrient (P2O5) content into account . The environmental suitability of the fields receiving animal waste was considered in prescribing the final application rate of solid and liquid manures generated by local animal production facilities . The degree of site suitability of the agricultural fields was also used to suggest manure management practices to minimise the socio-environmental risks and increase the nutrient use efficiency of the applied manure . The amount of ammonium nitrogen (NH4-N) that would be added to the soil by satisfying the P2O5 requirement using manure sources was also calculated and an applied NH4-N map was created . This map could be used to assist farmers identify additional nitrogen requirements after manure application. Sci Total Environ, 2002 Apr 15, 288(3), 167 - 81 Biological and chemical factors influencing shallow lake eutrophication: a long-term study; Lau SS et al.; The focus of eutrophication research has tended to be upon short-term and experimental studies . However, given the range of factors that can influence eutrophication dynamics, and that these matter over a range of time scales, some discrete, some continuous, eutrophication dynamics may only be fully investigated when long-term, time-series data are available . The present study aims to evaluate the interacting effects of abiotic processes and biotic dynamics in explaining variations of phytoplankton biomass in a eutrophic shallow lake, Barton Broad (Norfolk, UK) using a long-term data set . Multivariate statistical analysis shows that the inter-relationships between phytoplankton variability, nutrient and grazing factors were highly sensitive to seasonal periodicity . In spring phytoplankton biomass was related to phosphorus, nitrogen and silicon . In summer phytoplankton biomass was associated with phosphorus, nitrogen and zooplankton . In autumn phytoplankton was related to phosphorus, nitrogen, silicon and zooplankton . In winter, no significant relationship could be established between phytoplankton and environmental variables . This paper improves our understanding of the governing role of nitrogen, phosphorus, silicon and zooplankton upon phytoplankton variability, and hence, improves management methods for eutrophic lakes. Wei Sheng Yan Jiu, 1999 Mar 30, 28(2), 100 - 1 {Study on the contamination of algae and microcystins in water sources of Zhengzhou City}; Meng Y et al.; Planktonic algae and microcystins (MCYST) were detected constantly in water sources of Zhengzhou City from 1996 to 1997 . There is significant seasonal variation of the density of algae . The peak of algae occurring in February and December is about 1,068,000/L . The contents of MCYST in July, 1995 and in January, 1996 were over 200 ng/L . According to the Carlson's trophic state index(TSI), and indexes of total nitrogen, phosphorus, COD value and algae density, an eutrophication of water source having emerged in Zhengzhou is considered. Trends Plant Sci, 2002 Mar, 7(3), 118 - 25 Engineering crop plants: getting a handle on phosphate; Brinch-Pedersen H et al.; In plant seeds, most of the phosphate is in the form of phytic acid . Phytic acid is largely indigestible by monogastric animals and is the single most important factor hindering the uptake of a range of minerals . Engineering crop plants to produce a heterologous phytase improves phosphate bioavailability and reduces phytic acid excretion . This reduces the phosphate load on agricultural ecosystems and thereby alleviates eutrophication of the aquatic environment . Improved phosphate availability also reduces the need to add inorganic phosphate, a non-renewable resource . Iron and zinc uptake might be improved, which is significant for human nutrition in developing countries. J Environ Sci (China), 2002 Jan, 14(1), 76 - 8 Assessment of water pollution control strategies: a case study for the Dianchi Lake; Chen JN et al.; Lake eutrophication has increasingly become a major environmental issue in China . Although significant efforts have been made towards its resolution in the last decade, most of the implemented control strategies are fragmented, and the formation of policy lacks of sound scientific basis and long-term objectives . Taking the well-known Dianchi Lake as a case study, this paper presented a comprehensive assessment for the effectiveness of various eutrophication control strategies . It is expected that the concluding lessons would have a major implication to future eutrophication control. J Environ Sci (China), 2002 Jan, 14(1), 54 - 62 Cyanobacterial flora and the physico-chemical environment of six tropical fresh water lakes of Udaipur, India; Pandey J et al.; The cyanobacteria and physico-chemical environments of six tropical fresh water lakes of Udaipur, India were investigated . These lakes receive varying nutrient inputs from different sources . Altogether 51 species of cyanobacteria were recorded . Species composition varied between lakes and between seasons . Lake VI (Baghdara), which receives nutrients from natural sources only, differed considerably from the others in water chemistry and composition of dominant species . Lake II (Swaroop Sagar), eutrophied due to sewage inputs, was species poor . Non-diazotrophs, represented by 27 species, dominated during summer . With few exceptions, N2-fixing species, both heterocystous and unicellular diazotrophs (represented by 24 species), were dominant during winter . Microcystis aeruginosa, Phormidium sp . and Anabaena flos-aque were the dominant taxa of lakes characterized by sewage eutrophication . The study shows that both species diversity and community composition were affected by water chemistry. Environ Sci Technol, 2002 Feb 15, 36(4), 552 - 60 Emission inventories of NOx from commercial energy consumption in China, 1995-1998; Hao J et al.; Emissions of nitrogen oxides (NOx) in China are of great concern because of their impact on local air pollution as well as on regional environmental risks such as acid rain, eutrophication, tropospheric ozone, fine particulate matter, and loss of biodiversity . In this paper, total anthropogenic emissions of NOx in China during the past two decades are estimated on the basis of commercial energy consumption and NOx emission factors of different sectors and fuel types . Specifically, emission inventories of NOx from 31 provinces, 7 economic sectors, and 11 fuel types from 1995 to 1998 are evaluated and analyzed in detail, and the distribution of provincial-based average NOx emission intensity in 1998 is presented . It can be seen that the calculated national total emissions of NOx have rapidly increased from 4.76 Mt in 1980 to a peak value of about 12.03 Mt in 1996, with an average annual growth rate of 6% . However, instead of increasing, NOx emissions in 1997 and 1998 decreased by 0.37 Mt and 0.85 Mt, respectively, as compared to the peak in 1996 . In short, NOx emissions caused by energy use are mainly concentrated in the more populated and industrialized areas of China, i.e., the Eastern Central and Southeastern areas . These results imply that China's NOx emissions in the future may not become as high as previously expected which will be helpful for policy making to control local NOx pollution as well as to reduce acid rain and tropospheric ozone in East Asia. Sci Total Environ, 2002 Feb 21, 285(1-3), 97 - 105 Rapid assessment of macro algal cover on intertidal sediments in a nutrified estuary; Nedwell DB et al.; Macroalgal blooms have been considered to be an indicator of eutrophication . A new and rapid method is described for the assessment of macroalgal cover in the intertidal zone of estuaries . Macroalgal cover in the intertidal of the nutrient-enriched River Deben estuary was found to reach a maximum of 50% coverage, but this varied seasonally with the highest percentage cover during June and July . Macro-algae mats were particularly associated with areas of hard substrata providing suitable attachment points, rather than with the nutrient concentrations along the estuary . The occurrence of macroalgae may be more related to the substrate than to the nutrient status of the estuary. Ambio, 2001 Dec, 30(8), 522 - 8 Human impact on the fish diversity in the four largest lakes of Sweden; Degerman E et al.; The four largest Swedish lakes, Vanern, Vattern, Malaren, Hjalmaren, host important commercial fisheries for char, salmon, trout, whitefish, vendace (cisco), perch, pike-perch, pike and eel, i.e . highly diverse biological resources . Case studies illustrate physical, chemical and biological impacts on some of these commercial species caused by constructions of dams and ship canals, eutrophication, and overexploitation . Although some original species have been lost and a few new species have been added, the recent human interference has basically caused major shifts in dominance of the fish community structures because of eutrophication, alterations in the abundance of eel or crayfish, and due to overfishing . The latter is in some cases caused by the Great Lake Fishery Paradox--in an environment with several predators and competitors, but with ample food resources, especially salmonid fish but also species like pike-perch may adapt a life history favoring growth over sexual maturation . If harvested at a conventional size these populations will decline rapidly due to too small spawning stocks. Ambio, 2001 Dec, 30(8), 496 - 502 Sediment evidence of early eutrophication and heavy metal pollution of Lake Mälaren, central Sweden; Renberg I et al.; Lake Malaren is the water supply and recreation area for more than 1 million people in central Sweden and subject to considerable environmental concern . To establish background data for assessments of contemporary levels of trophy and heavy metal pollution, sediment cores from the lake were analyzed . Diatom-inferred lake-water phosphorus concentrations suggest that pre-20th century nutrient levels in Sodra Bjorkfjarden, a basin in the eastern part of Malaren, were higher (c . 10-20 micrograms TP L-1) than previously assumed (c . 6 micrograms TP L-1) . Stable lead isotope and lead concentration analyses from 3 basins (S . Bjorkfjarden, Gisselfjarden and Askofjarden) show that the lake was polluted in the 19th century and earlier from extensive metal production and processing in the catchment, particularly in the Bergslagen region . The lake has experienced a substantial improvement of the lead pollution situation in the 20th century following closure of the mining and metal industry . The lead pollution from the old mining industry was large compared to late-20th century pollution from car emissions, burning of fossil fuels and modern industries. Ambio, 2001 Dec, 30(8), 475 - 85 Recovery from eutrophication: experiences of reduced phosphorus input to the four largest lakes of Sweden; Wilander A et al.; In-lake concentration changes of phosphorus (P) and nitrogen (N) in lakes Vattern, Vanern, Malaren, and Hjalmaren in response to diminished input has been examined from the mid-1960s onwards . In the former two deep and oligotrophic lakes with slow water renewal, drastic reductions in P-input from the middle of 1970s caused just minor reductions in P-concentration over a very long time . At the same time accumulation occurred in the water mass of inorganic N and possible reasons are discussed . In the latter two mesotrophic to hypertrophic lakes, two shallow basins in L . Hjalmaren showed slow recovery due to release of P from sediments . The same basins and two basins in L . Malaren have suffered from N-deficiency, particularly during the pre-phosphorus reduction years, and nitrogen fixation was indicated . In two L . Malaren basins recovery of in-lake P concentrations was better than expected in comparison to the so-called IMSA-model for lake recovery from nutrient pollution . In the other five lakes/basins chlorophyll concentrations after 20 years were similar compared to those modeled. Zh Obshch Biol, 2001 Nov-Dec, 62(6), 512 - 24 {Structure and function of pelagic zooplankton in various types of lakes (using the example of small lakes in northwestern Russia}; Ivanova MB; Changes of structure and functioning of pelagic zooplankton under lake eutrophication were studied in a group of small (without outlet) lakes in southern Karelia and Leningrad region . The lakes were morphologically similar and located within the same climatic zone . Differences in their trophic status were connected with anthropogenic eutrophication . Correlation between species number and feeding resources of a lake is determined as: Y = (8.01 +/- 3.85) + (0.29 +/- 0.07)X1 + (6.75 +/- 1.52)X2, r2 = 0.95, (1) Y--number of zooplankton species, X1--average chlorophyll concentration for the season, mg/1; X2--average value of biochemical oxygen demand (expressed in mgC/1) . Average biomass of zooplankton for season also depends on food: logY = (-0.054 +/- 0.224) + (0.242 +/- 0.094)logX1 + (0.170 +/- 0.179)logX2, n = 13, r2 = 0.87, (2) Y--average zooplankton biomass for the season, kcal/m3, X1 and X2 the same as (1) . Increase in species number and zooplankton bimass determined primarily by Rotatoria occur in parallel to chlorophyll concentration and activity of bacteria . In acid lakes rotifers are not important in energy balance . In mezotrophic lakes two main energy paths are formed--through rotifers and through Crustacea . The role of rotifers is extremely important in eutrophic lakes where about 80% of energy paths through them . The ratio community production to energy consumption for the growing season is also depended on the community structure (species number, equitability, connectence): Y = (2.257 +/- 0.026) - (0.368 +/- 0.031)X1 + (5.160 +/- 0.442)X2, r2 = 0.99, (3) Y--average seasonal production of zooplankton, kcal/m2; X1--maximal meaning of Shannon index (bites), calculated on biomass value; X2--connectence of the community, calculated according Briand (1983) . Eutrophication changes the stability of lakes relative to external influences, while low productive lakes are very sensitive to the increase in nutrient load, high productive lakes are more influenced by changes in fish predation. Zhonghua Yu Fang Yi Xue Za Zhi, 2000 Mar, 34(2), 92 - 4 {Studies on algae and microcystin pollution in source water of Yellow River in Zhengzhou city}; Meng Y et al.; OBJECTIVE: To study the law of development of pollution with algae and microcystin (MC) in source water of Yellow River in Zhengzhou city . METHODS: Algae and MC were detected continuously for source water samples collected from B and S Water Works of Zhengzhou in 1998 . Microcystin was determined with high-sensitive ELISA . RESULTS: Monthly average density of algae was 1,439 x 10(4)/L in source water of B Water Works of Zhengzhou, with peak algae density of 4,762 x 10(4)/L in August, and that of S Water Works was 1,071 x 10(4)/L . Blue-algae of higher toxicity has become dominant species in source water from S water Works . Detection rate of microcystin was 70.83% in 24 samples collected from the two water works . CONCLUSION: According to Carlson's trophic state index (TSI), as well as other indices, such as total nitrogen, total phosphorus, chemical oxygen demands (COD) and algae density in water, source water in Zhengzhou has presented characteristics of eutrophication. Bioresour Technol, 2002 Mar, 82(1), 27 - 31 Growth rate of Ulva rigida in different Mediterranean eutrophicated sites; de Casabianca ML et al.; The growth of juvenile populations of Ulva rigida C . Agardh was measured by means of immersion in in situ cages against environmental parameters (temperature, incident light, salinity, dissolved inorganic nitrogen and dissolved reactive phosphorus) in four different eutrophicated southern sites: Channel of the Thau lagoon (France), Lido, Sacca Sessola and Fusina stations (Venice lagoon, Italy) . The growth curves as a function of temperature showed that, in all cases, the maximal temperature for Ulva growth was 17 degrees C (limitation in growth below 7 degrees C and above around 25 degrees C) . The growth analysis of these four sites showed seasonal differences . In the least eutrophicated and calmest Lido station, grazing and dissolved reactive phosphorus (seven times lower at Lido than at Thau) played a key role . At Thau and Fusina, which are eutrophicated and turbid environments, the incident light had a strong impact on growth . Sacca Sessola, with an intermediate position between the above two mentioned situations, showed the highest growth rate . The values and relative growth rate (RGR) curves of the Mediterranean and open-sea northern sites are discussed . In particular, the temperature defines the type of growth curve (unimodal or bimodal) and the incident light is responsible for the low Mediterranean RGR values (<10% day(-1)). Sci Total Environ, 2002 Jan 23, 282-283, 9 - 24 Agricultural nutrient inputs to rivers and groundwaters in the UK: policy, environmental management and research needs; Withers PJ et al.; Losses of nitrogen (N) and phosphorus (P) in land run-off and drainage from agricultural land can impair river water quality and may pose a potential health hazard . Losses of P are up to an order of magnitude smaller than those of N, but may be more significant with respect to freshwater eutrophication . At the field scale, research suggests that rates of nutrient loss are sensitive to both nutrient and land management, in particular, where nutrient inputs continuously exceed production requirements and where farming methods increase land vulnerability to run-off and erosion . A clear distinction can be made between N and P in the timescales over which inputs of these nutrients are buffered by terrestrial ecosystems against loss, which has implications for control strategies . At the river basin scale, any targets for reducing nutrient loss are best guided by site-specific information on their likely ecological impact, but this information rarely exists for UK rivers affected by eutrophication, and only general guidelines are available . True management of the environment requires integrated approaches which include both N and P taking account of differences in their source areas and delivery mechanisms, the vulnerability of land use and adoption of safe management options in relation to landscape characteristics and the sensitivity of the watercourse along its reach . For P, the identification of vulnerable zones represents a step forward to the management of the river basin in smaller definable units, which can provide a focus for safe management practices . This requires a better understanding of the linkages between nutrient sources, transport and impacts and is considered an urgent research priority. Proc R Soc Lond B Biol Sci, 2002 Feb 7, 269(1488), 289 - 94 History and timing of human impact on Lake Victoria, East Africa; Verschuren D et al.; Lake Victoria, the largest tropical lake in the world, suffers from severe eutrophication and the probable extinction of up to half of its 500+ species of endemic cichlid fishes . The continuing degradation of Lake Victoria's ecological functions has serious long-term consequences for the ecosystem services it provides, and may threaten social welfare in the countries bordering its shores . Evaluation of recent ecological changes in the context of aquatic food-web alterations, catchment disturbance and natural ecosystem variability has been hampered by the scarcity of historical monitoring data . Here, we present high-resolution palaeolimnological data, which show that increases in phytoplankton production developed from the 1930s onwards, which parallels human-population growth and agricultural activity in the Lake Victoria drainage basin . Dominance of bloom-forming cyanobacteria since the late 1980s coincided with a relative decline in diatom growth, which can be attributed to the seasonal depletion of dissolved silica resulting from 50 years of enhanced diatom growth and burial . Eutrophication-induced loss of deep-water oxygen started in the early 1960s, and may have contributed to the 1980s collapse of indigenous fish stocks by eliminating suitable habitat for certain deep-water cichlids . Conservation of Lake Victoria as a functioning ecosystem is contingent upon large-scale implementation of improved land-use practices. J Environ Qual, 2002 Jan-Feb, 31(1), 338 - 49 Gas dynamics in eutrophic lake sediments affected by oxygen, nitrate, and sulfate; Liikanen A et al.; In many freshwater ecosystems, the contents of NO3- and SO4(2-) have increased, whereas O2 has been depleted due to the increased acid and nutrient loads . These changes may affect carbon turnover and the dynamics of the major greenhouse gases CO2, CH4, and N2O . We studied the effects of O2, NO3-, and SO4(2-) availability on carbon mineralization, and fluxes of CO2, CH4, and N2O in the sediments of hyper-eutrophic Lake Kevaton, Finland . Undisturbed sediment cores from the deep (9 m) and shallow (4 m) profundal were incubated in a laboratory microcosm with oxic and anoxic water flows with NO3- or SO4(2-) concentrations of 0, 30, 100, 300, and 2000 microM . The carbon mineralization rate (i.e., the sum of released CO2-C and CH4-C) was not affected by the oxidants . However, the oxidants did change the pathways of carbon degradation and the release of CH4 . All of the oxidants depressed CH4 fluxes in the shallow profundal sediments, which had low organic matter content . In the deep profundal sediments rich in organic matter, the CH4 release was reduced by O2 but was not affected by SO4(2-) (the effect of NO3- was not studied) . There was an increase in N2O release as the overlying water NO3- concentration increased . Anoxia and highly elevated NO3- concentrations, associated with eutrophication, increased drastically the global warming potential (GWP) of the sedimentary gases in contrast to the SO4(2-) load, which had only minor effects on the GWP. J Environ Qual, 2002 Jan-Feb, 31(1), 280 - 6 Bioavailable phosphorus in runoff from alfalfa, smooth bromegrass, and alfalfa-smooth bromegrass; Zemenchik RA et al.; Runoff from sloping landscapes cropped with established alfalfa (Medicago sativa L.) may contain bioavailable P (BAP) which accelerates eutrophication of surface water bodies . Such BAP exists as either dissolved reactive P (DRP) or bioavailable reactive particulate P (BPP) . We hypothesized that before and after harvest, sod-forming smooth bromegrass (Bromus inermis Leyss.) or alfalfa-smooth bromegrass mixtures would have less BAP, DRP, and BPP runoff losses than taprooted alfalfa . Swards established in 1992 near Lancaster, WI were subjected to a 72 mm simulated rainfall applied for 1 h in 1993 and 1994 to forage regrowth at 4 and 6 wk after first harvest and immediately (0 wk) after second harvest . Hourly BAP losses for all sward types were 82% less when 1.5 Mg ha(-1) of forage dry matter was present . High DRP losses (>0.050 kg ha(-1)) were associated with high DRP concentrations (>7.1 micromol L(-1)) and high surface soil P concentrations (>59 mg kg(-1)) resulting from broadcast maintenance P fertilizer . High BPP losses (>0.035 kg ha(-1)) were associated with high runoff volumes (>24 mm) and sediment concentrations (>2 g L(-1)) . Summed over all 6 rainfall simulations, total BAP loss was only 0.07 kg ha(-1) at the 6 wk stage of regrowth compared with 0.35 at 4 wk, and 0.41 at 0 wk . Moreover, there was no significant difference between sward types for DRP concentration, DRP loss, or BAP loss . We conclude that avoiding excessive defoliation was more effective at reducing BAP losses than specific forage species selection. Proc Natl Acad Sci U S A, 2002 Feb 5, 99(3), 1395 - 8 Epub 2002 Jan 29. Anthropogenic modification of New England salt marsh landscapes; Bertness MD et al.; Salt marshes play a critical role in the ecology and geology of wave-protected shorelines in the Western Atlantic, but as many as 80% of the marshes that once occurred in New England have already been lost to human development . Here we present data that suggest that the remaining salt marshes in southern New England are being rapidly degraded by shoreline development and eutrophication . On the seaward border of these marshes, nitrogen eutrophication stimulated by local shoreline development is shifting the competitive balance among marsh plants by releasing plants from nutrient competition . This shift is leading to the displacement of natural high marsh plants by low marsh cordgrass . On the terrestrial border of these same marshes, shoreline development is also precipitating the invasion of the common reed, Phragmites, by means of nitrogen eutrophication caused by the removal of the woody vegetation buffer between terrestrial and salt marsh communities . As a consequence of these human impacts, traditional salt marsh plant communities and the plants and animals that are dependent on these habitats are being displaced by monocultures of weedy species. Environ Pollut, 2002, 116(2), 309 - 17 Fish community responses to pulp and paper mill effluents at the southern Lake Saimaa, Finland; Karels AE et al.; The fish community in sublittoral and profundal waters, at stony shores, and densities of vendace larvae were studied in the southern Lake Saimaa, Finland . The objective was to investigate the possible recovery of fish populations after modernizations at the pulp and paper mills discharging into the lake . Sublittoral and profundal waters were studied by gill net trial fishings, stony shores by electrofishing, and vendace larvae by beach seine . The research area was divided in a polluted (0.5-4.0% effluent), an intermediate (0.1-0.5%) and a 'clean' reference area . The fish community in sublittoral and profundal waters in the lake was dominated (> 60%) by perch and roach . Relative abundance of fish was highest in the polluted area, and lowest in the reference area . The number of species caught was similar among areas . The abundance of bleak and ruffe was highest in the polluted area, while the abundance of vendace and whitefish was highest in the intermediate and reference area . The fish fauna of stony shores in the lake was dominated by bullhead, stone loach and minnow, densities were lowest at polluted shores and highest in the intermediate area . Minnow, apparently a more sensitive species to pulp mill effluents, were not caught at the most polluted shores . The catch of vendace larvae was similar among areas, larvae were also caught in the vicinity of the mills . Compared with before the modernization at the mills, the relative abundance of perch in the polluted area was increased, ruffe decreased, while populations of whitefish and vendace showed signs of recovery . These changes may be explained by the reduced nutrient load and toxicicity of pulp mill effluents . At present, the fish community in the polluted area can be considered typical for a moderate eutrophication. Water Sci Technol, 2001, 44(11-12), 93 - 100 Environmental impacts to the Everglades ecosystem: a historical perspective and restoration strategies; Chimney MJ et al.; The Everglades is a vast subtropical wetland that dominates the landscape of south Florida and is widely recognized as an ecosystem of great ecological importance . As a result of anthropogenic disturbances over the past 100 years (i.e., agricultural and urban development, eutrophication resulting from stormwater runoff, changes in hydrology and invasion of exotic species), the biotic integrity of the entire Everglades is now threatened . To protect this valuable resource, the state of Florida and the Federal Government, in cooperation with other interested parties, have developed a comprehensive restoration strategy that addresses controlling excess nutrient loading and reestablishment of a more natural hydrology . These efforts include building approximately 17,000 ha of treatment wetlands, referred to as Stormwater Treatment Areas, to treat surface runoff before it is discharged into the Everglades . We briefly discuss the history of the Everglades in the context of environmental disturbance and outline the steps being taken to ensure its survival for future generations. Water Sci Technol, 2001, 44(11-12), 591 - 8 Buffer zones promoting oligotrophication in golf course runoffs: fiddler crabs as estuarine health indicators; George RY et al.; Nitrogen pollution above a threshold level induces a eutrophication process in coastal creek ecosystems and consequently impacts on the water quality . The remedy for this scenario is the introduction of methods to enhance oligotrophication by means of constructed wetlands and buffer zones . This paper discusses new data on nitrogen flux and population changes in the primary consumers in the Bradley Creek ecosystem, adjacent to the Duck Haven Golf Course in southeastern North Carolina . In 1998-99, over different seasons, density distribution of the field populations of the fiddler crab Uca minax, was monitored as an indicator of environmental health . A control site at Whiskey Creek, adjacent to the University Center for Marine Sciences, was monitored in the same period since this site is not influenced by any golf course nutrient flux . The results pointed out that threshold level for optimum population density in Spartina grandiflora salt marsh is 0.1 mg/L of nitrates . A dense crab population, adjacent to the golf course with a buffer zone, was indicative of restoration of the estuarine ecosystem . A model, involving the use of constructed wetlands for oligotrophication, is being prepared on the basis of studies conducted by the University of South Alabama for a stormwater wetland constructed adjacent to the university's golf course. Water Sci Technol, 2001, 44(11-12), 289 - 94 Determining ecologically acceptable nutrient loads to natural wetlands for water quality improvement; Keenan LW et al.; Natural wetlands often function as nutrient sinks, reducing nutrient inputs into lakes and streams . P loading from anthropogenic sources has significantly affected many natural wetlands . This paper describes a method to determine an acceptable P load to natural wetlands based on ecological principles . This approach can be used to determine how much P can be assimilated without diminishing species diversity and, thereby, sets a limit for cultural eutrophication of natural wetlands . The basis for determining an acceptable load is management of risk to species diversity by determination of the maximum area of a wetland that can be put at risk while preserving biodiversity of the overall wetland system . Two cases are distinguished: 1) simple-stress, where growth of the affected area immediately increases risks for species loss, and 2) subsidy-stress, where growth of the affected area first benefits then diminishes net species diversity. Water Sci Technol, 2001, 44(11-12), 171 - 6 Removal of nutrients from combined sewer overflows and lake water in a vertical-flow constructed wetland system; Gervin L et al.; Lake Utterslev is situated in a densely built-up area of Copenhagen, and is heavily eutrophicated from combined sewer overflows . At the same time the lake suffers from lack of water . Therefore, a 5,000 m2 vertical flow wetland system was constructed in 1998 to reduce the phosphorus discharge from combined sewer overflows without reducing the water supply to the lake . During dry periods the constructed wetland is used to remove phosphorus from the lake water . The system is designed as a 90 m diameter circular bed with a bed depth of c . 2 m . The system is isolated from the surroundings by a polyethylene membrane . The bed medium consists of a mixture of gravel and crushed marble, which has a high binding capacity for phosphorus . The bed is located within the natural littoral zone of the lake and is planted with common reed (Phragmites australis) . The constructed wetland is intermittently loaded with combined sewer overflow water or lake water and, after percolation through the bed medium, the water is collected in a network of drainage pipes at the bottom of the bed and pumped to the lake . The fully automated loading cycle results in alternating wet and dry periods . During the initial two years of operation, the phosphorus removal for combined sewer overflows has been consistently high (94-99% of inflow concentrations) . When loaded with lake water, the phosphorus removal has been high during summer (71-97%) and lower during winter (53-75%) partly because of lower inlet concentrations . Effluent phosphorus concentrations are consistently low (0.03-0.04 mg/L) . Ammonium nitrogen is nitrified in the constructed wetland, and total suspended solids and COD are generally reduced to concentrations below 5 mg/L and 25 mg/L, respectively . The study documents that a subsurface flow constructed wetland system can be designed and operated to effectively remove phosphorus and other pollutants from combined sewer overflows and eutrophicated lake water. J Environ Qual, 2001 Nov-Dec, 30(6), 2105 - 12 Rapid incidental phosphorus transfers from grassland; Preedy N et al.; In Britain, frequent rainfall means that there is a high potential for rapid, direct (incidental) losses of phosphorus (P) to occur after fertilizer or manure application . However, despite the known contribution of P to the eutrophication of water bodies in Britain, such incidental transfers have received little experimental attention . To rectify this, we used lysimeter plots (each 3 x 10 m) to investigate incidental transfers in a composite of overland and lateral subsurface flow (0-27 cm) following the application of different P sources . The treatments used were triple super phosphate (TSP), dairy slurry (Slurry), an equal mix of TSP plus slurry (TSP + Slurry), and no P (Zero P) . The treatments were applied to wet soil at a rate of 29 kg ha(-1) . In the following 169 h, 48.8 mm rainfall (intensity < or =3 mm h(-1)) resulted in total phosphorus (TP) exports between 1.8 and 2.3 kg ha(-1) . A single 4-h period (with overland flow) accounted for 33 to 46% of overall loads from the P-amended treatments . Concentrations in discharge from TSP + Slurry and TSP peaked at 11000 microg TP L(-1) (67-68% as reactive P < 0.45 microm (RP<0.45) . Slurry peaked at 7000 microg TP L(-1), 66% as particulate TP (>0.45 microm) and 20% as RP<0.45 . Even in subsurface flow, concentrations exceeded 3000 microg TP L(-1) for all P-amended treatments . Incidental TP concentrations in plot discharge were up to 110-fold higher than those considered eutrophic in inland waters . We suggest that targeting short-term management decisions for P applications is the most immediately viable method to mitigate P loss and benefit the environment. J Environ Qual, 2001 Nov-Dec, 30(6), 2018 - 25 Evaluation of the phosphorus index in watersheds at the regional scale; Birr AS et al.; Agricultural losses of phosphorus (P) in runoff are a primary cause of eutrophication in many freshwater systems . A modified version of the P Index originally developed jointly by the USDA (Agricultural Research Service {ARS}, Cooperative State Research, Education, and Extension Service {CSREES}, and Natural Resources Conservation Service {NRCS}) was used to prioritize P loss vulnerability at the regional scale from 60 watersheds located within Minnesota using readily available data related to the transport and sources of P . This modified version of the P Index was created for a regionally based analysis of the index . Validation of the P Index rating was conducted using long-term water quality monitoring data consisting of total P concentrations collected from watersheds and lakes . The modified version of the P Index produced a strong correlation between P Index rating and total P stream monitoring data in watersheds (r2 = 0.70) excluding the Red River Basin . An equally strong relationship was observed between P Index rating and lake water quality (r2 = 0.68) using the modified P Index . The P Index ratings for the Red River Basin showed good correlation with observed total P stream monitoring data (r2 = 0.51); however, the P Index ratings were smaller than in other basins . The results of this study suggest that, with certain limitations, the P Index can be used at the regional scale to prioritize P loss vulnerability using state and national databases . Regional P Index ratings represent the average risk for agricultural land within the entire watershed. Zhonghua Zhong Liu Za Zhi, 2001 Mar, 23(2), 96 - 9 {The relationship between cyanotoxin (microcystin, MC) in pond-ditch water and primary liver cancer in China}; Yu S et al.; OBJECTIVE: To explore the relationship between primary liver cancer (PLC) and MC in drinking pond-ditch water . METHODS: Epidemiological and ecological assays, Meta-analysis and risk assessment were used in this study . Cyanotoxin (Microcystin, MC) in the water of different sources was detected by ELISA . The F344 and HBVx transgenic mice were used to confirm the promotion effect on PLC and the synthetically carcinogenic effect of HBV, aflatoxin and MC . RESULTS: Using Meta-analysis the results of six case-control studies showed that the pooled odds ratio (OR) was 2.46 (95% CI 1.69-2.59), population attributable rick (PAR) was 30.39% (95% CI, 23.30%-37.47%), heterogeneity test P > 0.05 . Eutrophication led to cyanobacterial bloom in the pond-ditch water . Cyanotoxin released from dead cyanobacteria was hepatotactic tumor promoter . In HBVx transgenic rats, hepatocellular carcinoma was induced by the joint administration of aflatoxin B1 and cyanotoxin . Epidemiological study showed that the recombined index of HBsAg, aflatoxin-albumin adducts and drinking of pond-ditch water correlated with PLC mortalities in 13 townships . CONCLUSION: Microcystin in the pond-ditch water is a hepatotactic toxin which can induce hepatitis and promote development of hepatocellular carcinoma . The combined effect of microcystin, HBV and aflatoxin may be responsible for the endemicity of PLC. Water Res, 2002 Jan, 36(1), 49 - 58 Biochemical model of glucose induced enhanced biological phosphorus removal under anaerobic condition; Wang N et al.; Enhanced biological phosphorus removal (EBPR) is playing an increasingly important role in controlling the eutrophication phenomenon in natural waters . It is believed that substrates other than acetate exert significant effects on the EBPR process . In this research, it was found that glucose could be used as the dominant substrate to induce and maintain a successful EBPR process . However, compared to the conventional EBPR process using acetate as the dominant substrate, it was found that less PO4-P was released into the medium and 3-hydroxyvalerate (3-HV) enriched poly-beta-hydroxyalkanoate (PHA), rather than 3-hydroxybutyrate (3-HB) enriched PHA, was accumulated during the anaerobic condition . According to the experimental results, a new biochemical model is hypothesized for the anaerobic metabolism of glucose . It is reasoned that the predominance of 3-HV enriched PHA is employed to balance the internal redox during the anaerobic condition . The Entner-Doudoroff (ED) pathway is likely used for anaerobic glucose metabolism when the bacteria demonstrate good EBPR performance, because the ED pathway necessitates the use of polyphosphate for energy purposes. J Environ Health, 2001 Dec, 64(5), 25 - 32 Sources of the eutrophication problems associated with toxic algae: an overview; Pitois S et al.; Blooms of cyanobacteria (toxic blue-green algae) can produce health and environmental hazards in water, including water used for drinking or recreational purposes . How, why, and when these blooms are produced, as well as how to deal with them, are questions whose answers are vital to the safeguarding of public health in regions where the algae occur . The blooms are linked to eutrophication of water, and this paper discusses the eutrophication problems, their nature, and their relevance to the production of cyanobacteria . Nutrient limitations on algal productivity are considered, as is the involvement of the atmosphere, the storage of nutrients in soils, and the influence of anthropogenic activity. Int J Hyg Environ Health, 2001 Nov, 204(2-3), 143 - 55 Spatial impact of the Oder river plume on water quality along the south-western Baltic coast; Schernewski G et al.; The Oder (Odra) river is the most important nutrient source and pollutant for the south-western Baltic Sea . Adjacent German-Polish coastal waters, the Oder (Szczecin) Lagoon and the Oder (Pomeranian) Bight therefore suffer from severe eutrophication and water quality problems . At the same time, summer (bathing) tourism is the most important economical factor in this coastal zone, especially on the islands of Usedom and Wolin . On the basis of model simulations and remote sensing data we analysed the spatial extent and variability of the Oder river plume in the lagoon and the Balic Sea in common summer situations and during the extreme Oder flood in August 1997 . Water quality shows pronounced gradients between coastal waters and open Baltic Sea . In the lagoon, it usually takes more than 6 weeks until Oder water enters the large western bay, the Kleines Haff . During transport, degradation, transformation and sedimentation processes alter the water quality and prevent the inner coast of Usedom from direct impact of polluted Oder water . Ongoing nutrient supply promotes intensive algal proliferation in all parts of the lagoon and contributes to the low water transparency . Oder water passing the lagoon and entering the Baltic Sea is transported over long distances in narrow bands along the shore . Under easterly winds the water quality near well-known spas on Usedom is reduced due to Oder river plume impact . Upwelling effects can have negative impact on water quality, too . Intensive blooms of potentially toxic blue-green algae species, are the rule in the lagoon and frequent in the Oder Bight in summer . They are a hazard and limit the acceptance of swimming beaches at the inner coast of Usedom . Practical consequences of variable water quality gradients e.g . on hygienic water sampling are discussed. Ying Yong Sheng Tai Xue Bao, 2001 Aug, 12(4), 590 - 2 {Ecological engineering for eutrophication control in lake}; Sun G et al.; An ecological engineering was conducted for eutrophication control in the Nanhu Lake of Changchun . In 1996, the removal of phosphorus by harvesting aquatic macrophytes and fishes was 149.6 kg and 189.9 kg, respectively, and the phosphorus fixed in molluscs was 153.4 kg . The total output was 492.9 kg, which amounted approximately to the annual phosphorus input to the lake . After ecological engineering, the water quality turned better, the TP concentration in lake water decreased, the phytoplankton density reduced, and the number of phytoplankton species increased . The roles of molluscs and fish in controlling lake eutrophication should be further studied . Ecological engineering is an ideal method to control the eutrophication of urban lakes. Ambio, 2001 Sep, 30(6), 369 - 75 Multipond system: a sustainable way to control diffuse phosphorus pollution; Yin C et al.; Diffuse pollution from agricultural land is one of the main causes for lake eutrophication . Multipond systems, an ancient invention in China, are composed of many tiny ponds and ditches, scattered in agricultural fields . After a long period of research in an experimental watershed in Liuchahe, it was found that multipond systems constitute diffuse pollution control . They have a large capacity for water storage and serve to control the export of water, suspended matter, and phosphorus . Multipond systems significantly reduce runoff velocity . Sediments and phosphorus retained in the Liuchahe watershed were 14.38 x 10(6) and 7016 kg yr-1, respectively (area 691.6 ha) . Irrigation provides an effective way to recycle and remove phosphorus . The use of multipond systems is a sustainable way to recycle valuable nutrients and reduce their discharge and thus pollution of downstream lakes. Water Sci Technol, 2001, 44(7), 63 - 8 Analysis of the hydrology and flow of nitrogen in 17 Danish catchments; Andersen HE et al.; In the search for tools for evaluating the effects of national action plans combating diffuse nutrient pollution causing eutrophication of surface waters, a study of the nitrogen (N) flow in 17 Danish agricultural catchments was carried out . Data on N input and N harvest for the agricultural year of 1993/1994 was obtained from questionnaire surveys facilitating the set up of N balances . Net export of N from the catchments measured at the outlet was obtained from time-series of stream water chemistry and discharge from 1993-1997 . N leaching from the root zone of each field was calculated using an empirical model . A physically based lumped rainfall-runoff model was used for separating the hydrograph time-series into three runoff components: baseflow, interflow and overland flow . Large regional variations in net N input were found ranging from 62 kg N ha(-1) yr(-1) in the loamy eastern part of the country dominated by cereal production to 137 kg N ha(-1) yr(-1) in the western part characterised by less fertile sandy soils and dominated by animal husbandry . N leaching from the root zone showed a corresponding variation with regional averages ranging from 34.5 kg N ha(-1) yr(-1) to 90.9 kg N ha(-1) yr(-1) . No similar regional pattern could however be found regarding net N export, and no relationship could be established between net N export and root zone N leaching . This finding was ascribed to a varying and in some catchments very high (>80%) N retention during subsurface transport to the stream . The hydrological modelling revealed that loamy catchments had a high proportion of quick flow (overland flow + interflow), whereas baseflow dominated the sandy catchments . Further, a highly significant relationship between N retention and proportion of quick flow was found emphasising the importance of understanding the hydrological pathways . This should be taken into consideration when evaluating the N loading of surface waters resulting from a given agricultural practice and the effects of possible changes in this practice. Water Sci Technol, 2001, 44(7), 35 - 40 Study of the distribution of non-point source pollution in the watershed of the Miyun Reservoir, Beijing, China; Wang X et al.; Nitrogen and phosphorus are major nutrients to cause eutrophication to degrade the water quality of the Miyun Reservoir, a very important drinking water source of Beijing in China . These are mainly from non-point sources . The watershed in Miyun County is selected as the study region with a total area of 1400 km2 . Four typical monitoring catchments and two experimental units were used to monitor the precipitation, runoff, sediment yield and pollutant loading related to various land uses in the meantime . The results show that the total nutrient loss amount of TN and TP is 898.07 t/a, and 40.70 t/a, respectively, in which nutrient N and P carried by runoff is 91.3% and 77.3%, respectively . There is relatively heavier soil erosion at the northern mountain area whereas the main nutrient loss occurs near the northeast rim of the reservoir . Different land uses influence the loss of non-point source pollutants . The amount of nutrient loss from agricultural land per unit is the highest, nutrient loss from forestry is the second highest and that from grassland is the lowest . However, due to the variability of land use areas, agricultural land contributes the greatest amount of TP and forestry lands the greatest amount of TN. Water Sci Technol, 2001, 44(6), 35 - 46 Multipurpose use and water quality challenges in Lac de Guiers (Senegal); Cogels FX et al.; Lac de Guiers (Guiers Lake) is a shallow lake in West Africa . Its waters are used mainly for irrigation and drinking water . Recent engineering in the Senegal River Valley has changed the lake's functioning and led to new water quality conditions . This article describes the water quality effects of the management of the lake and use of its waters, with special emphasis on salinity and eutrophication. Water Sci Technol, 2001, 44(6), 19 - 26 Eutrophication study of twenty reservoirs in Taiwan; Chang SP et al.; Taiwan is an island off the southeastern coast of China with total area of roughly 36,000 km2 . The geographic position of Taiwan is between 21degrees 45' 25" to 25 degrees 56' 31" north latitude and 119 degrees 18' 3"to 124 degrees 34' 30" east longitude and includes both tropical and subtropical areas . The study was carried out at twenty main reservoirs in Taiwan area from 1994 to 1998 . The study revealed that the water quality of most reservoirs gradually deteriorated during the study period . Total phosphorus concentrations over 60 microg/L were observed in 12.5% of these reservoirs in 1994, but in 22.2% of these reservoirs in 1998 . Total nitrogen concentrations over 1.0 mg/L were observed in 37.5% of these reservoirs in 1994, but in 94.4% of these reservoirs in 1998 . Secchi disc transparency below 2 m was observed in 75% of these reservoirs in 1994, but in 83.3% of these reservoirs in 1998 . Chlorophyll a concentrations over 15 mg/m3 were observed in 12.5% of these reservoirs in 1994, but in 27.8% of these reservoirs in 1998 . The TN:TP mass ratios (wt/wt) of all the studied reservoirs except Akungting Reservoir, Fongshan Reservoir, and Chengching Reservoir are higher than 16 . The study results on nutrient limitation indicated that phosphorus is the primary limiting nutrient in Taiwan reservoirs except Akungting Reservoir, Fongshan Reservoir, and Chengching Reservoir. Nature, 2001 Nov 8, 414(6860), 166 - 7 Nitrate flux in the Mississippi River; McIsaac GF et al.; Increased delivery of biologically available nitrogen to estuaries and coastal oceans in recent decades has been linked to eutrophication and seasonal hypoxia in the northern Gulf of Mexico and elsewhere . We have developed a model that accounts for 95% of annual variation in delivery of nitrate to the Gulf of Mexico by the Mississippi River in 1960-98 . Retrospective analysis indicates that this nitrate flux could have been reduced by 33% if the use of nitrogen-containing fertilizer in the Mississippi River basin had been cut by 12%. Ambio, 2001 Aug, 30(4-5), 217 - 21 Fish stocks in the Baltic Sea: finite or infinite resource? Ojaveer E, Lehtonen H. Human-induced environmental changes, especially eutrophication, and fluctuations of natural environmental conditions under the changes in climate and solar activity affect the reproduction and growth of various fish species and communities in the Baltic Sea . The importance of human impacts has increased considerably during the last decades, overshadowing in many cases natural factors . High exploitation rates have depressed some valuable fish species and affected the species dominance hierarchy . Oxygen depletion in deeper layers progressively deteriorates the living conditions of certain marine species . Mass immigration of nonindigenous species with ballast waters can seriously affect ecosystems and fish stocks . The summary effect of these variables upon marine, relict and freshwater species can yield unexpected results . Fish resources should be properly assessed and managed by their natural units (populations) . Based on cyclic fluctuations of global climatic processes, composition of long-term forecasts on changes in the structure and abundance of fish fauna should be started. Ambio, 2001 Aug, 30(4-5), 202 - 9 The meltdown of biogeographical peculiarities of the Baltic Sea: the interaction of natural and man-made processes; Leppakoski E et al.; The biogeographical peculiarities of the Baltic Sea have developed since the last glacial period . The characteristic mixture of marine, brackish water, and freshwater species, and relicts from previous periods in the Baltic, is threatened by ongoing environmental changes . This review focuses on the recent impacts of nonindigenous species, eutrophication, and a temporary oxygen deficit in the deep basins, on the biogeographical integrity of the Baltic on different spatial and time scales . Today the biota of brackish waterbodies are exposed to each other because of the breakdown in geographical barriers due to shipping traffic, leading to an exchange of species and further homogenization of aquatic animal and plant life worldwide. Ambio, 2001 Aug, 30(4-5), 184 - 9 Eutrophication, harmful algal blooms and species diversity in phytoplankton communities: examples from the Baltic Sea; Kononen K; Understanding the mechanisms that govern biological diversity in various environments is one of the greatest challenges for the scientific community of today . Compared to terrestrial and benthic habitats, mechanisms regulating species diversity in planktonic ecosystems have been dealt with relatively little . This is mainly due to the scarcity of the experimental evidence from field studies where the multitude of spatiotemporal scales have been covered with sufficient resolution . This paper discusses the peculiarities of the aquatic system as a growth environment for phytoplankton in comparison to terrestrial/connected systems . Examples of the regulation of species diversity in the Baltic Sea are presented. Ambio, 2001 Aug, 30(4-5), 172 - 8 The history of cyanobacterial blooms in the Baltic Sea; Finni T et al.; Long-term information on possible changes in cyanobacterial blooms in the Baltic Sea, formed mainly by Nodularia spumigena and Aphanizomenon sp., was sought in published records in historical (years 1887-1938) and modern (years 1974-1998) phytoplankton data sets . Old and new sampling methods and fixatives were tested to improve the comparison of data that had been collected and analyzed in different ways . A hundred years ago, plankton was mainly of interest as a source of fish food; eutrophication problems were only locally reported from the coast, mainly in southern haffs and the receiving waters of larger cities . There were few recordings of open-sea blooms before World War II . Abundances of Nodularia spumigena and Aphanizomenon sp . were low in the old material, and 137 summer samples from 1887-1938 showed no peak abundance . High abundances are common in the new material, and the range of the numbers of both taxa has increased markedly relative to the old material . Since the 1960s, cyanobacterial blooms have been common in the open sea in both the Baltic proper and the Gulf of Finland, indicating high availability of nutrients. Mar Environ Res, 2001 Oct, 52(4), 323 - 49 Benthic macrofauna changes in areas of Venice lagoon populated by seagrasses or seaweeds; Sfriso A et al.; Two areas of the Venice lagoon populated by seagrasses (three stations covered by Cymodocea nodosa (Ucria) Asherson, Zostera marina Linnaeus, Zostera noltii Hornemann) or seaweeds (two stations: one covered by Ulva rigida C . Agardh and another at present without seaweed biomass) were monitored by means of six surveys over a year in order to study macrofaunal composition and seasonal changes . The seagrass stations showed a mean species richness (28-30 S m(-2)), individual abundance (1854-4018 N m(-2)) and biomass (22.3-37.7 g m(-2) ash-free-dry-weight, AFDW) ca . 3-8 times higher than those populated by seaweeds (10-15 S m(-2), 494-1395 N m(-2) and 5.6-13.7 g m(-2) AFDW) . Differences among seagrass or seaweed stations were much lower . The Ulva-dominated station showed a macrofauna completely different both from the other stations and the communities recorded ca . 30 years ago, before the prolific growth of Ulva . In this station, frequent biomass decompositions and anoxic crises created critical conditions for life favouring organisms with reduced life cycles, younger individuals and the epifaunal species instead of the infaunal ones . In particular, Ulva grazers and scrapers such as Gammarus aequicauda Stock and Gibbula adriatica Philippi were found to be by far the most abundant species, whereas the taxa characteristic of the associations found in the past, in the presence of seagrasses or seaweeds and typical of low eutrophicated environments, appear strongly reduced . Marked differences in the macrophyte dominance and in the bio-physico-chemical variables which characterise the main environmental conditions of the Venice lagoon support the different distribution and composition of macrofaunal communities . Seaweed stations appear mainly governed by the seasonal cycles of these un-rooted macrophytes which, by alternating periods of production and decomposition, are responsible for the drastic reduction of macrofauna biodiversity and biomass . Conversely, seagrass stations exhibit a better oxidisation of the environment and show conditions more favourable for macrofauna colonisation, especially in the presence of macrophytes which are characterised by very well developed below-ground systems such as Cymodocea nodosa. Chemosphere, 2001 Nov, 45(6-7), 827 - 34 Seasonal variations in phosphorus species in the surface sediments of the Gulf of Riga, Baltic Sea; Aigars J; The redox-dependent variations in concentrations of phosphorus at two different accumulation bottom areas were investigated in the Gulf of Riga (Baltic Sea) between December 1993 and January 1995 . The sediment samples from nine sampling occasions were analyzed for phosphorus forms and redox potential . The average concentrations of total phosphorus measured in 0-1 cm (65 and 89 micromol P g(-1) for sites G5 and T3, respectively) were among the highest reported from the entire Baltic Sea . Redox-dependent "mobile" phosphorus (MP) contributed more than 50% of total in the uppermost-oxidized centimeter, whereas in reduced layers it was 16-18% throughout the year . The significant differences (ANOVA, P<0.01) among months of inorganic phosphorus (IP) concentration at 0-1 cm were observed at site G5 due to temporary accumulation of mobile phosphorus mediated by redox-dependent bacteria activity during summer . On the contrary no accumulation was observed at T3 probably as a result of low redox potential caused by high accumulation rates and low bioturbation . Although the water column above sediments remained oxic throughout the investigation period, the redox potential at site T3 was close to the redoxcline (i.e., +230 mV) during summer . Further increase of eutrophication might lead to development of anoxic conditions at sediment-water interface and that in turn will result in rapid release of redox-dependent phosphorus stored in surface sediments . The availability of excess phosphorus will further enhance eutrophication in partly phosphorus-limited Gulf of Riga. Ecotoxicol Environ Saf, 2001 Oct, 50(2), 143 - 52 Do food processing industries contribute to the eutrophication of aquatic systems? Tusseau-Vuillemin MH. Eutrophication is the enrichment of water bodies with plant nutrients and precursors, typically nitrogen, phosphorus, and organic matter . There exists a "natural" and slow eutrophication, which, over geological times, turns a lake into a marsh and then dries it entirely . Today, however, eutrophication is mostly referred to the human process that "results in the stimulation of an array of symptomatic changes, among which increased production of algae and macrophytes, deterioration of water quality and other symptomatic changes are found to be undesirable and interfere with water uses" as defined by the OECD in 1982 . This undesirable process is observed mostly in enclosed water bodies, such as lakes, but also in some rivers, some estuaries, and some coastal zones . In most freshwater systems, phosphorus has been identified as the "limiting nutrient" to phytoplankton development . This nutrient is brought to aquatic environments from rock weathering, soil leaching, and rain (natural sources), but also and mostly from agricultural runoff and domestic sewage . Some food processing industries (meat, vegetables, cheese processing) also contribute significantly to the phosphorus budget, even though the pollution may be due to floor and utensil cleaning rather than to direct food wastes . Environ Sci Technol, 2001 Oct 15, 35(20), 4126 - 31 Stability of phosphorus within a wetland soil following ferric chloride treatment to control eutrophication; Sherwood LJ et al.; Addition of iron and aluminum compounds has become an increasingly popular method to regulate phosphorus eutrophication in lakes and reservoirs . It has been proposed that ferric chloride addition to agricultural runoff entering the northern Everglades could provide a means for enhancing natural mechanisms of phosphorus removal from the wetland . In this study we added ferric chloride to Everglades water spiked with 32PO4, incubating the resulting precipitates in microcosms simulating the Everglades ecosystem . 32P activity and reduction-oxidation (redox) potentials were monitored to determine if the 32P was released into the overlying water column due to iron reduction . Results of redox potential measurements and 32P activity indicate that although reducing conditions exist in the soil, on average less than 1% of the added 32P was measured in the water column during the 139-day incubation . Ferric chloride addition thus might prove an effective means of long-term phosphorus retention in the Florida Everglades and perhaps other wetland systems. Sci Total Environ, 2001 Oct 20, 278(1-3), 113 - 25 Phosphorus losses in subsurface flow before and after manure application to intensively farmed land; McDowell RW et al.; A study was conducted to examine the loss of P in subsurface flow from three cultivated soils of varying soil P concentrations . Measurements were made in flow waters from the soils before applying manure and then 3 weeks after sowing the soils to grass . An additional measurement of P in flow waters was made 1 year later . Dissolved reactive P (DRP) concentrations measured in flow water before (0.15-0.20 mg l(-1)) and after (0.39-0.51 mg l(-1)) manure application exceed current estimates of those required to promote surface water eutrophication (0.05 mg l(-1)) . Concentrations of DRP1 year after manurial application increased compared to 3 weeks after application and was attributed to the slow movement of P down the cultivated soil . Concentrations of soil P were significantly increased down the soil profile and attributed to the P saturation of soils before manurial application . The results suggest that despite the establishment of fast growing grass, P concentrations would not be mitigated in the short-term (= 1 year), due to the large contribution of P in subsurface pathways. Parasitology, 2001 Sep, 123(Pt 3), 257 - 69 Long-term dynamics of Ligula intestinalis and roach Rutilus rutilus: a study of three epizootic cycles over thirty-one years; Kennedy CR et al.; Data are presented on 2 full epizootic cycles and the start of a third of Ligula intestinalis in roach Rutilus rutilus in a small lake, and the relationships of these cycles to the densities of rudd, Scardinius erythrophthalmus, and Great Crested Grebes, Podiceps cristatus, over 31 years . The parasite was introduced to the lake by P . cristatus in 1973 at a time when the roach population had increased in response to eutrophication to a level at which individual fish growth was stunted and the hithero dominant rudd population had declined in numbers as a consequence of inter-specific competition with roach . Ligula prevalence peaked at 28% in only 2 years: thereafter parasite-induced host mortality caused a decline in the roach population, releasing fish from stunting and allowing the rudd population to recover . The consequent improved growth of roach individuals and their short life-span reduced Ligula transmission rates and prevalence levels declined to approximately 1% although Ligula nevertheless persisted for a further 10 years . Following a massive winter-kill of the fish populations in 1984-1985, fish and Ligula numbers declined to barely detectable levels and the parasite disappeared from samples . Rudd recovered first, then roach and interspecific competition again led to a decline in rudd numbers . This increase in roach numbers led to a decrease in roach growth rates, which coincided with the re-colonization of the lake by Ligula . This second epizootic of Ligula peaked within 2 years in 1991-1992, when up to 78% of roach were infected with a maximum abundance of 2.2 parasites and intensity of 21 parasites . Heavy parasite-induced mortality of roach led to a decline in numbers, an improvement in individual growth rate and a reduction of Ligula transmission rates such that the epizootic died out in 1996 . Similar conditions of roach numbers and growth prevailed at the start of a third cycle in 1998 . The course of events over the second cycle was so similar to that of the first that it confirms the interpretations of that cycle . Comparison with other localities shows that epizootics of Ligula always coincide with rapid increases in roach numbers, for whatever cause, and stunted growth, which together attract piscivorous birds . At the start of a cycle Ligula is a major determinant of the population dynamics of the roach, but at the end of the cycle the fish population dynamics determine those of the parasite . The cycles are not regulated and the roach-Ligula system is inherently unstable. Vet Hum Toxicol, 2001 Oct, 43(5), 294 - 7 The toxicology of microcystin-LR: occurrence, toxicokinetics, toxicodynamics, diagnosis and treatment; Bischoff K; Cyanobacterial blooms occur worldwide and present an increasing problem due to eutrophication of lakes . Microcystins, especially microcystin-LR, are microcyclic heptapeptide hepatotoxins and are the most common and potent toxins associated with cyanobacteria . Microcystin is rapidly taken up by hepatocytes through carrier-mediated transport . Once in the hepatocyte, microcystin causes structural damage to the cell indirectly by inhibiting protein phosphorylases 1 and 2A, which are needed for regulation of structural proteins of the cell . Acute liver hemorrhage and death occur with high doses of microcystin-LR, which is also a potent tumor promoter in laboratory rats . The significance of microcystin to human health has been debated; however, poisoning in humans has occurred due to contaminated dialysis water . Microcystin in contaminated drinking water may be the cause of elevated rates of primary liver cancer in some areas of China . Problems with hepatotoxic cyanobacteria have been most seen in livestock . Treatment of confirmed microcystin toxicosis in livestock is likely to be unrewarding, so prevention is important . Wild mammals, birds, fish, insects, and microinvertebrates may also be affected by microcystin. J Environ Qual, 2001 Sep-Oct, 30(5), 1829 - 35 Using phosphorus concentration in the soil solution to predict phosphorus desorption to water; Torrent J et al.; The growing concerns about water eutrophication have made it urgent to restrict losses of phosphorus (P) from agricultural soils and to develop methods for predicting such losses . In this work, we used the paradigm of P sorption-desorption curves to confirm the hypothesis that the amount of dissolved reactive phosphorus (DRP) released to a dilute electrolyte tends to be proportional to the concentration of DRP in the soil solution raised to a power that decreases with increasing solution to soil ratio (W) . The hypothesis was tested for a group of 12 widely ranging European agricultural soils fertilized with P in excess of crop needs . Phosphorus desorption was studied under near-static and turbulent conditions in laboratory experiments . The concentration of DRP in the 1:1 soil to water extract (P1:1) was used as a proxy for the DRP concentration in the soil solution . The amount of desorbed P was found to be correlated with P1:1 raised to a power that decreased from 0.7 to 0.9 at W=100 to 0.2 to 0.4 at W=10 000 . Correlation was not improved by introducing additional variables related to P sorption-desorption properties . Olsen P was found to be of lower predictive value than P1:1 . Also, the index of degree of soil saturation with phosphorus (DSSP) based on oxalate extraction failed to predict P desorption . The fact that P1:1 seemingly predicts P desorption accurately for a wide range of soils makes it potentially useful in areas of high soil diversity. Huan Jing Ke Xue, 2001 Jul, 22(4), 104 - 7 {Relationship between eutrophication control and reservoir operation}; Jia H et al.; Choosing Miyun Reservoir as a research background, the spatial distribution characteristics of water quality in the reservoir were analyzed, and the relationship between reservoir operation and-eutrophication control was discussed . With the assistance of water quality model and the monitored data, measures that wiping off the nutrients combined with the flood prevention operation was proposed . At last, the feasibility of the measure was also discussed. Water Res, 2001 Oct, 35(15), 3517 - 36 Integrated modelling of eutrophication and organic contaminant fate & effects in aquatic ecosystems . A review; Koelmans AA et al.; Eutrophication and contamination with micropollutants have been major problems in water quality management . Both problems have been subjected to extensive research and modelling but traditionally are treated separately . Traditional simulation models for aquatic systems can be categorised as eutrophication models, contaminant fate models, food web models and food chain bioaccumulation models . Because they are single issue models, many interactions and feedbacks between the food web, nutrient and toxicant cycles are missed . Linking these models is essential to evaluate the fate and risks of contaminants in systems with changing nutrient loading, to assess the natural attenuation of contaminants or to understand the selfpurifying capacity of ecosystems . Combination of the single issue models requires inclusion of 'interaction processes' to account for the coupling between the (sub-) model types, such as organic carbon cycling . toxicity, transport and accumulation of organic contaminants in the food chain, and bottom up versus top down control of primary production and nutrient cycling . This review first provides a brief overview of traditional approaches in modelling eutrophication, contaminant fate, food web dynamics and food chain bioaccumulation . Second, five existing integrated eutrophication, fate and/or effects models are reviewed . Third, the gaps and limitations in modelling the four types of interaction processes are discussed . It is concluded that these models are invaluable tools to focus attention to feedback mechanisms that are often overlooked, to identify dominating processes in ecosystems, to formulate counterintuitive hypotheses on ecosystem functioning, or to assess short term risks of acutely toxic stressors . However, the potential of integrated models for long term simulations of contaminant exposure . food chain bioaccumulation and effects to higher trophic levels remains limited, mainly because of principal limitations in food web modelling . In contrast, the potential of integrated models for long term simulations of contaminant fate is better because the environmental distribution of contaminants is mainly determined by the major abiotic compartments and by biotic compartments at the base of the food chain. Water Sci Technol, 2001, 44(2-3), 329 - 36 Effect of residence times on River Mondego estuary eutrophication vulnerability; Duarte AS et al.; The south arm of the Mondego estuary, located in the central western Atlantic coast of Portugal, is almost silted up in the upstream area . So, the water circulation is mostly driven by tides and the tributary river Pranto discharges . Eutrophication has been taking place in this ecosystem during last twelve years, where macroalgae reach a luxuriant development covering a significant area of the intertidal muddy flat . A sampling program was carried out from June 1993 to June 1994 . Available data on salinity profiles and on nutrients loading into the south arm were used in order to get a better understanding of the ongoing changes . River Pranto flow discharges, controlled by a sluice, were also monitored . Integral formulations are typically based on assumptions of steady state and well-mixed systems and thus cannot take into account the space and time variability of estuarine residence times, due to river discharge flow, tidal coefficients, discharge(s) location and time of release during the tidal cycle . This work presents the hydrodynamics modelling (2D-H) of this system in order to estimate the residence times variability and to assess their effect on the estuarine eutrophication vulnerability, contributing to better environmental management strategies selection. J Environ Monit, 1999 Aug, 1(4), 403 - 7 An investigation of the origin and mobility of phosphorus in freshwater sediments from Bort-Les-Orgues Reservoir, France; Ruban V et al.; In order to assess the origin and the potential mobility of phosphorus (P) in the sediment of the Bort-Les-Orgues Reservoir, France, two sequential extraction schemes, i.e., the SMT (modified Williams method) and the Golterman schemes, were compared . Finally, the potential mobility of P in this sediment was estimated from results of sequential extraction . The SMT method appeared to be more satisfactory than the Golterman method, which is in accordance with results from a study currently carried out in the framework of the European programme Standards, Measurements and Testing . Iron-bound P and organic P were the dominant forms of P in the sediment; these forms are likely to be released at the sediment/water interface in case of anoxia and could diffuse into the water column, thus increasing the risk of eutrophication in this sensitive reservoir . The P stock (330 +/- 66 t) is not negligible and should be taken into account in any restoration project of the reservoir . The SMT procedure seems promising and will provide, in the near future, a valuable tool for water managers in the field of lake restoration. J Environ Monit, 1999 Feb, 1(1), 51 - 6 Selection and evaluation of sequential extraction procedures for the determination of phosphorus forms in lake sediment; Ruban V et al.; In order to achieve comparable measurements in the determination of phosphate forms in freshwater sediments, the Standards, Measurements and Testing Programme (formerly BCR) of the European Commission has launched a project the first step of which was to select and evaluate collaboratively existing extraction procedures . This was carried out through expert consultations and a literature survey, and was followed by the organisation of a first interlaboratory study for the evaluation of four sequential extraction schemes, one of which was selected as the most promising method for achieving comparability . This scheme, a modified version of the Williams protocol, was further tested in a second interlaboratory study . The so-called SMT extraction scheme seems promising and will provide, in the near future, a valuable tool for water managers in the field of lake restoration . It will be particularly helpful in estimating the stock of P potentially available, hence the risk of eutrophication due to internal P release. Water Res, 2001 Sep, 35(13), 3157 - 67 Lake ecosystem health assessment: indicators and methods; Xu FL et al.; A set of ecological indicators including structural, functional, and system-level aspects were proposed for a lake ecosystem health assessment, according to the structural, functional, and system-level responses of lake ecosystems to chemical stresses including acidification, eutrophication and copper, oil and pesticide contamination . The structural indicators included phytoplankton cell size and biomass, zooplankton body size and biomass, species diversity, macro- and micro-zooplankton biomass, the zooplankton phytoplankton ratio, and the macrozooplankton microzooplankton ratio . The functional indicators encompassed the algal C assimilation ratio, resource use efficiency, community production, gross production/respiration (i.e . P/R) ratio, gross production standing crop biomass (i.e . P/B) ratio, and standing crop biomass unit energy flow (i.e . B/E) ratio . The ecosystem-level indicators conisisted of ecological buffer capacities, energy, and structural energy . Based on these indicators, a direct measurement method (DMM) and an ecological modeling method (EMM) for lake ecosystem health assessment were developed . The DMM procedures were designed to: (1) identify key indicators; (2) measure directly or calculate indirectly the selected indicators; and, (3) assess ecosystem health on the basis of the indicator values . The EMM procedures were designed to: (1) determine the structure and complexity of the ecological model according to the lake's ecosystem structure; (2) establish an ecological model by designing a conceptual diagram, establishing model equations, and estimating model pararmeters; (3) compare the simulated values of important state variables and process rates with actual observations; (4) calculate ecosystem health indicators using the ecological model; and, (5) assess lake ecosystem health according to the values of the ecological indicators . The results of a case study demonstrated that both methods provided similar results which corresponded with the lake's actual trophic state. J Environ Qual, 2001 Jul-Aug, 30(4), 1474 - 80 Phosphorus sorption characteristics of estuarine sediments under different redox conditions; Pant HK et al.; Phosphorus (P) plays a major role in eutrophication of aquatic systems . Estuarine sediments could function as sources or sinks for P to the overlying water column depending upon their physico-chemical characteristics . Understanding of P sorption phenomena in estuarine sediments is important in regulating the P availability in estuaries . Phosphorus sorption characteristics of sediments from the Indian River Lagoon, Florida, USA, were determined to examine the role of selected physico-chemical properties of the sediments on soluble reactive P status in estuary water . Mean equilibrium P concentrations (EPCo) of 0.75 mg L(-1) and mean P sorption maxima (Smax) of 32.2 mg kg(-1) were obtained under anaerobic conditions, compared with EPCo of 0.05 mg L(-1) and Smax of 132.7 mg kg(-1) under aerobic conditions . The higher EPCo values under anaerobic conditions and the greater Smax values under aerobic conditions were associated with amorphous and poorly crystalline iron . These results suggest that sediments enriched with amorphous and poorly crystalline forms of iron act as an excellent reservoir for P by adsorbing excessive P in aerobic sediment zones and releasing it upon burial under anaerobic conditions . This study also indicates that P compounds in sediments independently maintain equilibrium with P in solutions . Thus, heterogeneous systems like soil and sediment simply behave as a mixture of homogeneous surfaces as far as their P sorption characteristics are concerned, and hence can be successfully described by the Langmuir and Freundlich models. J Environ Qual, 2001 Jul-Aug, 30(4), 1324 - 30 Effects of tillage and phosphorus placement on phosphorus runoff losses in a grain sorghum-soybean rotation; Kimmell RJ et al.; Phosphorus enhances eutrophication of fresh water bodies . This study was conducted to determine the influence of tillage and P placement on P losses in runoff water from a somewhat poorly drained soil (Woodson silt loam {fine, smectitic, thermic Abruptic Argiaquoll}, 1.0-1.5% slope) in a grain sorghum {Sorghum bicolor (L.) Moenchl-soybean {Glycine mar (L.) Merr} rotation . Chisel-disk-field cultivate (ChT), ridge-till (RT), and no-till (NT) in combination with 0 kg P ha(-1) or 24 kg P ha(-1) broadcast or knifed (applied prior to planting grain sorghum) were studied . Runoff volume and losses of sediment and P were summed over the growing season . Significant interactions between tillage and P placement for soluble P losses were found . For example, soluble P loss in 1999 for NT-broadcast in grain sorghum was 358 g ha(-1); significantly greater than 31 g ha(-1) for NT-knife or 23 g ha(-1) for NT-check . Similar results were found for RT but no such differences were found for ChT . Bioavailable P losses were generally highest with broadcast P placement and for NT and RT . Total P losses were significantly higher at 959 g ha(-1) with broadcast P on grain sorghum in 1998, compared with 521 g ha(-1) for the check and 659 g ha(-1) for the knifed P applications . Total P losses in 1999 for soybeans were only 18 g ha(-1) for NT, which was significantly lower than 75 g ha(-1) for ChT and 66 g ha(-1) for RT . The results indicate that broadcast P applications on RT and NT will increase P losses, but the influence of tillage was not consistent. Ambio, 2001 May, 30(3), 127 - 34 Quantification of anthropogenic threats to lakes in a lowland county of central Sweden; Brunberg AK et al.; An evaluation of the negative effects caused by anthropogenic influence on lake ecosystems was performed, using data from 143 catchments in Uppsala County, Sweden . The study included i) technical encroachments; i.e . construction of dams, dikes, etc . as well as effects of drainage of land; ii) pollution, i.e . eutrophication, acidification, and contamination by toxic substances; iii) introduction of nonnative species; and iv) exploitation of species populations . Severe damage was caused mostly by drainage of land followed by pollution by toxic substances and, to a smaller extent, introduction of nonnative species and eutrophication . Most lakes were subject to several types of disturbances, interacting in a complex pattern, which made it difficult to link the visible effects to the true causes of the disturbance . Future lake management should include analyses of all disturbances to the lake catchments, taking into account the historical perspective, in order to balance the threats/damages, in an analysis of the possibilities for maintaining biodiversity and sustainability in the ecosystems. Environ Toxicol Chem, 2001 Jul, 20(7), 1511 - 6 Acute sensitivity of nematode taxa to CuSO4 and relationships with feeding-type and life-history classification; Bongers T et al.; The acute sensitivity to CuSO4 of a broad range of nematode taxa was analyzed in order to assess the potential of changes to nematode community structure to serve as a practical tool for the bioindication of heavy-metal pollution . An easy-to-use experimental set-up was developed along with an appropriate mathematical response model in order to quantify the response characteristics of nematodes to CuSO4 pressure . Three similar experiments were conducted using water, dune sand, and sandy soil as media, each of which was subjected to 12 increasing concentrations of CuSO4 . In total, 130 response curves representing 70 nematode taxa were produced and analyzed . CuSO4 concentrations were normalized for differences in efficiency among media due to different adsorption . At low CuSO4 concentrations, many taxa exhibited stimulation rather than inhibition regarding recovery efficiency . At higher concentrations, the concentration level at which 50% of the nematode population was recovered after a 24-h incubation (recovery concentration 50% {RC50}) varied widely among taxa and ranged from 0.01 to 4 mM/L CuSO4 (normalized to water) . Stimulation of recovery efficiency and RC50 were negatively correlated with the colonizer-persister (C-P) classification of taxa, which discriminates nematodes according to their reproductive potential . The maturity index, which relates to a nematode community's state of disturbance and eutrophication, was negatively correlated with CuSO4 concentration . The properties of the applied test method are discussed as are the relationships between the investigated short-term toxicity effects and long-term toxicity processes in the field . From the large range of observed RC50 values, it is concluded that a meaningful sensitivity classification of nematodes should be possible and thus would allow for a sensitive bioindication of heavy-metal pollution . From the correlation between RC50 and C-P classification, the authors further conclude that the maturity index will, in addition to enrichment and disturbance, respond to heavy-metal pollution and thus may serve as a general indicator of soil health. Environ Toxicol, 2001 Jun, 16(3), 225 - 33 Apoptotic effect of cyanobacterial extract on rat hepatocytes and human lymphocytes; Mankiewicz J et al.; Toxic cyanobacterial blooms are an increasing problem in Poland . The production of cyanobacterial toxins and their presence in drinking and recreational waters represent a growing danger to human and animal health . This is connected with the increase of cyanobacterial biomass caused by excessive eutrophication of the water ecosystem . There is evidence that cyanobacterial hepatotoxins can act as a potent promoter of primary liver cancer . The apoptotic effect of microcystins in Polish cyanobacterial bloom samples on rat hepatocytes and human lymphocytes was observed using light and fluorescence microscopy, flow cytometry, and electrophoretic analysis . The incubation time needed to observe the first morphological apoptotic changes in hepatocytes was approximately 30 min; however, the characteristic biochemical changes in DNA were not observed even after 120 min . In lymphocyte cultures the morphological changes characteristic for apoptosis were observed after 24 h of incubation and a 48-h incubation was found to be optimal for analysis of internucleosomal DNA fragmentation, which is one of the main biochemical hallmarks of programmed cell death . These cells are an easily isolated and inexpensive material for medical diagnostics . Therefore the apoptotic changes, together with the clastogenic effect seen in lymphocyte cultures, are proposed as a future analytical method for these toxins. J Environ Qual, 2001 May-Jun, 30(3), 992 - 8 Effects of alum and aluminum chloride on phosphorus runoff from swine manure; Smith DR et al.; Phosphorus (P) runoff from fields fertilized with swine (Sus scrofa domesticus) manure may contribute to eutrophication . The objective of this study was to evaluate the effect of aluminum sulfate (alum) and aluminum chloride applications to swine manure on P runoff from small plots cropped to tall fescue (Festuca arundinacea Shreb.) . There were six treatments in this study: (i) unfertilized control plots, (ii) untreated manure, (iii) manure with alum at 215 mg Al L(-1), (iv) manure with aluminum chloride at 215 mg Al L(-1), (v) manure with alum at 430 mg Al L(-1), and (vi) manure with aluminum chloride at 430 mg Al L(-1) . Manure application rates were equivalent to approximately 125 kg N ha(-1) . Alum and aluminum chloride additions lowered soluble reactive phosphorus (SRP) levels from about 130 mg P L(-1) to approximately 30 mg P L(-1) at low rates . At high rates, SRP levels in swine manure were around 1 mg P L(-1) . Soluble reactive P concentrations in runoff were 5.50, 3.66, 3.00, 0.87, 0.87, and 0.55 mg P L(-1), for normal manure, low alum, low aluminum chloride, high alum, high aluminum chloride, and unfertilized control plots, respectively . Hence, high alum and aluminum chloride reduced SRP concentrations in runoff by 84% and were not statistically different from SRP concentrations in runoff from unfertilized control plots . These data indicate that treating swine manure with alum or aluminum chloride could result in significant reductions in nonpoint-source P runoff. J Environ Qual, 2001 May-Jun, 30(3), 1009 - 15 Phosphorus losses in furrow irrigation runoff; Westermann DT et al.; Phosphorus (P) often limits the eutrophication of streams, rivers, and lakes receiving surface runoff . We evaluated the relationships among selected soil P availability indices and runoff P fractions where manure, whey, or commercial fertilizer applications had previously established a range of soil P availabilities on a Portneuf silt loam (coarse-silty, mixed, superactive, mesic Durinodic Xeric Haplocalcid) surface-irrigated with Snake River water . Water-soluble P, Olsen P (inorganic and organic P), and iron-oxide impregnated paper-extractable P (FeO-Ps) were determined on a 0.03-m soil sample taken from the bottom of each furrow before each irrigation in fall 1998 and spring 1999 . Dissolved reactive phosphorus (DRP) in a 0.45-microm filtered runoff sample, and iron-oxide impregnated paper-extractable P (FeO-Pw), total P, and sediment in an unfiltered runoff sample were determined at selected intervals during a 4-h irrigation on 18.3-m field plots . The 1998 and 1999 data sets were combined because there were no significant differences . Flow-weighted average runoff DRP and FeO-Pw concentrations increased linearly as all three soil P test concentrations increased . The average runoff total P concentration was not related to any soil P test but was linearly related to sediment concentration . Stepwise regression selected the independent variables of sediment, soil lime concentration, and soil organic P extracted by the Olsen method as related to average runoff total P concentration . The average runoff total P concentration was 1.08 mg L(-1) at a soil Olsen P concentration of 10 mg kg(-1) . Soil erosion control will be necessary to reduce P losses in surface irrigation runoff. Environ Sci Pollut Res Int, 2001, 8(2), 95 - 102 Forest ecosystems and the changing patterns of nitrogen input and acid deposition today and in the future based on a scenario; Busch G et al.; A global assessment of the impact of the anthropogenic perturbation of the nitrogen and sulfur cycles on forest ecosystems is carried out for both the present-day {1980-1990} and for a projection into the future {2040-2050} under a scenario of economic development which represents a medium path of development according to expert guess {IPCC IS92a} . Results show that forest soils will receive considerably increasing loads of nitrogen and acid deposition and that deposition patterns are likely to change . The regions which are most prone to depletion of soils buffering capacity and supercritical nitrogen deposition are identified in the subtropical and tropical regions of South America and Southeast Asia apart from the well known 'hotspots' North-Eastern America and Central Europe . The forest areas likely to meet these two risks are still a minor fraction of the global forest ecosystems, though . But the bias between eutrophication and acidification will become greater and an enhanced growth triggered by the fertilizing effects of increasing nitrogen input cannot be balanced by the forest soils nutrient pools . Results show increasing loads into forest ecosystems which are likely to account for 46% higher acid loads and 36% higher nitrogen loads in relation to the 1980-1990 situation . Global background deposition of up to 5 kg N ha-1 a-1 will be exceeded at more than 25% of global forest ecosystems and at more than 50% of forest ecosystems on acid sensitive soils . More than 33% of forest ecosystems on acid sensitive soils will receive acid loads which exceeds their buffering capacity . About 25% of forest areas with exceeded acid loads will receive critical nitrogen loads. Environ Monit Assess, 2001 Jun, 69(1), 63 - 83 Stream phosphorus transport in the Lake Tahoe basin, 1989-1996; Hatch LK et al.; Lake Tahoe is undergoing the initial stages of cultural eutrophication due to human alteration of the airshed and watershed . The lake's switch from nitrogen (N) to phosphorus (P) limitation has been attributed primarily to atmospheric N loading . This places an increased importance on controlling watershed movement of P to the lake . A stream water quality monitoring data set consisting of nine streams in the Lake Tahoe basin has been analyzed to characterize the spatiotemporal variation of P delivery to the lake . This data is from the Lake Tahoe Interagency Monitoring Program (LTIMP), which provides scientific data for planning and regulatory agencies to address environmental problems in the Lake Tahoe basin . Results indicate that P delivery (concentrations, loads) varies greatly at interannual, seasonal, and spatial scales . Annual and seasonal total P (TP) concentrations can vary up to three orders of magnitude in a given stream and are strongly associated with suspended sediment . Particulate P is the major form of P transported by Tahoe streams and was strongly correlated with percent surficial geologic deposits, which are primarily located near streams . Tahoe streams with the highest annual P concentrations often had the lowest annual P loads, and visa versa . P loading is greatest during the spring snowmelt (75% of annual average) . Potential watershed parameters influencing P delivery to Lake Tahoe have been identified as precipitation, basin area, basin steepness, and road and human development coverage . Results also suggest that human development impacts on stream P loads are most prevalent during high precipitation years . Identification and quantification of stream sediment and P sources such as streambanks and impervious surface is necessary to aid in watershed restoration efforts. Environ Monit Assess, 2001 May, 68(3), 297 - 312 Marine eutrophication: a proposed data analysis procedure for assessing spatial trends; Kitsiou D et al.; A methodology for the discrimination of the different trophic levels at a spatial scale in the marine environment is proposed using spatial analysis methods and non-parametric statistics . Phytoplankton cell number, being a representative parameter to express trophic trends in the marine ecosystem is selected for the methodology development; Saronicos Gulf, Greece is used for the case study . The proposed stepwise methodology includes interpolation for assessing the spatial distribution of phytoplankton cell number, division of the Gulf into a number of quadrates, development of a scale characterising trophic levels and finally characterisation of the trophic state of each quadrate using non-parametric statistics . The advantages of this methodology and the potential applications in coastal management studies are also discussed. Huan Jing Ke Xue, 2001 Jan, 22(1), 98 - 101 {Phosphorus loss potential of soil-water in sites of the main rice-yield area in the Northern Zhejiang}; Zhang Z et al.; Phosphorus (P) loss potential and its environmental impact from soil-water were surveyed in Jiashan Yuyao, Deqing and Yuhang, named main rice-yield areas in Northern Zhejiang province China . High P input has resulted in soil P accumulation . Higher soil Olsen-P contributed its bio-available P, water extracted P and increased soil P loss potential . The role of P in paddy soils is of environmental rather than agronomic concern in the process of soil P build-up . During the no-rice time, total P (TP) concentration in the various water including ditch drain inside/outside field, field surface water and pipe drain et al are over the critical values associated with accelerated waters eutrophication . The average proportion of dissolved reactive P (DRP) concentration in TP was 40%, however, these current DRP levels in partly ditch drain outside field and surface or ground water in no-rice time could not caused serious impact to the outside waters nearby rice-yield agriculture area . No significant line correlation between soil P tests and P in field surface water was found in no-rice time due to differences in field tillage among rice-yield areas, while P application increased both soil P and its correspondingly field surface P level after rice was planted at the same time. Mar Pollut Bull, 2001 Feb, 42(2), 87 - 90 Ospar 98/3: an environmental turning point or a flawed decision? Bellamy D, Wilkinson P. While the problems of over-fishing and eutrophication continue largely unchecked, the Ospar Commission, which exists to improve the quality of European seas, requires governments, the public and the oil companies to find 20 billion Pounds to remove millions of tons of steel to demonstrate its commitment to the mantra that 'the seas are not dustbins' . The decision, taken in 1998, was made despite a paucity of evidence to identify the environmental impact redundant rigs create, despite the absence of scientific support to demonstrate that removal is the best practicable environmental option and in the knowledge that the decision had more to do with a green anti-oil agenda than with improving marine quality . It may be shown in the fullness of time not to be in the best interests of the environment . Moreover, and perhaps more importantly, the manner in which the decision was made is lacking in important respects. Mar Pollut Bull, 2001 Feb, 42(2), 149