Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

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    Future water quality monitoring - Adapting tools to deal with mixtures of pollutants in water resource management
    Altenburger, R. ; Ait-Aissa, S. ; Antczak, P. ; Backhaus, T. ; Barcelo, D. ; Seiler, T. ; Brion, F. ; Focks, A. - \ 2015
    Science of the Total Environment 512-513 (2015). - ISSN 0048-9697 - p. 540 - 551.
    effect-directed analysis - environmental risk-assessment - tandem mass-spectrometry - community tolerance pict - waste-water - estrogenic compounds - surface waters - conceptual-framework - organic-chemicals - zebrafish embryos
    Environmental quality monitoring of water resources is challenged with providing the basis for safeguarding the environment against adverse biological effects of anthropogenic chemical contamination from diffuse and point sources. While current regulatory efforts focus on monitoring and assessing a few legacy chemicals, many more anthropogenic chemicals can be detected simultaneously in our aquatic resources. However, exposure to chemical mixtures does not necessarily translate into adverse biological effects nor clearly shows whether mitigation measures are needed. Thus, the question which mixtures are present and which have associated combined effects becomes central for defining adequate monitoring and assessment strategies. Here we describe the vision of the international, EU-funded project SOLUTIONS, where three routes are explored to link the occurrence of chemical mixtures at specific sites to the assessment of adverse biological combination effects. First of all, multi-residue target and non-target screening techniques covering a broader range of anticipated chemicals co-occurring in the environment are being developed. By improving sensitivity and detection limits for known bioactive compounds of concern, new analytical chemistry data for multiple components can be obtained and used to characterise priority mixtures. This information on chemical occurrence will be used to predict mixture toxicity and to derive combined effect estimates suitable for advancing environmental quality standards. Secondly, bioanalytical tools will be explored to provide aggregate bioactivity measures integrating all components that produce common (adverse) outcomes even for mixtures of varying compositions. The ambition is to provide comprehensive arrays of effect-based tools and trait-based field observations that link multiple chemical exposures to various environmental protection goals more directly and to provide improved in situ observations for impact assessment of mixtures. Thirdly, effect-directed analysis (EDA) will be applied to identify major drivers of mixture toxicity. Refinements of EDA include the use of statistical approaches with monitoring information for guidance of experimental EDA studies. These three approaches will be explored using case studies at the Danube and Rhine river basins as well as rivers of the Iberian Peninsula. The synthesis of findings will be organised to provide guidance for future solution-oriented environmental monitoring and explore more systematic ways to assess mixture exposures and combination effects in future water quality monitoring.
    Seabirds, gyres and global trends in plastic pollution
    Franeker, J.A. van; Law, K.L. - \ 2015
    Environmental Pollution 203 (2015). - ISSN 0269-7491 - p. 89 - 96.
    fulmars fulmarus-glacialis - northern fulmars - particle pollution - marine-environment - surface waters - south-atlantic - ingestion - debris - ocean - sea
    Fulmars are effective biological indicators of the abundance of floating plastic marine debris. Long-term data reveal high plastic abundance in the southern North Sea, gradually decreasing to the north at increasing distance from population centres, with lowest levels in high-arctic waters. Since the 1980s, pre-production plastic pellets in North Sea fulmars have decreased by ~75%, while user plastics varied without a strong overall change. Similar trends were found in net-collected floating plastic debris in the North Atlantic subtropical gyre, with a ~75% decrease in plastic pellets and no obvious trend in user plastic. The decreases in pellets suggest that changes in litter input are rapidly visible in the environment not only close to presumed sources, but also far from land. Floating plastic debris is rapidly “lost” from the ocean surface to other as-yet undetermined sinks in the marine environment.
    Aquatic risk assessment of pesticides in Latin America
    Carriquiriborde, P. ; Mirabella, P. ; Waichman, A. ; Solomon, K. ; Brink, P.J. van den; Maund, S.J. - \ 2014
    Integrated Environmental Assessment and Management 10 (2014)4. - ISSN 1551-3793 - p. 539 - 542.
    surface waters - south-america - amazon state - brazil - ecosystems - cypermethrin - herbicide - argentina - impact
    Latin America is anticipated to be a major growth market for agriculture and production is increasing with use of technologies such as pesticides. Reports of contamination of aquatic ecosystems by pesticides in Latin America have raised concerns about potential for adverse ecological effects. In the registration process of pesticides, all countries require significant data packages on aquatic toxicology and environmental fate. However there are usually no specific requirements to conduct an aquatic risk assessment. To address this issue, the Society of Environmental Toxicology and Chemistry organised a workshop that brought together scientists from academia, government, and industry to review and elaborate on aquatic risk assessment frameworks that can be implemented into regulation of pesticides in Latin America. The workshop concluded that the international framework for risk assessments (protection goals, effects, and exposure assessments, risk characterization and risk mitigation) is broadly applicable in Latin America, but needs further refinement for the use in the region. Some of the challenges associated with these refinements are discussed in the paper. It was recognized that there is potential for data sharing both within and outside of the region where conditions are similar. However there is a need for research to compare local species and environmental conditions to those in other jurisdictions to be able to evaluate the applicability of data used in other countries. Development should also focus on human resources as there is a need to build local capacity and capability, and scientific collaboration and exchange between stakeholders in industry, government, and academia is also important. The meeting also emphasised that, although establishing a regionally relevant risk assessment framework is important, this also needs to be accompanied by enforcement of developed regulations and good management practices to help protect aquatic habitats. Education, training, and communication efforts are needed to achieve this.
    Speciation of heavy metals in River Rhine
    Vega, F.A. ; Weng, L. - \ 2013
    Water Research 47 (2013)1. - ISSN 0043-1354 - p. 363 - 372.
    donnan membrane technique - field-flow fractionation - dissolved organic-matter - fresh-waters - trace-metals - chemical speciation - humic substances - model parameters - surface waters - natural-waters
    Chemical speciation of Zn, Cu, Ni, Cd and Pb in River Rhine was studied by measuring free ion concentration and distribution in nanoparticles, and by comparing the measurement with speciation modeling. Concentrations of free metal ions were determined in situ using Donnan Membrane Technique (DMT). The percentage of free over total (filtered) metal concentration is 52%, 33%, 2.6%, 0.48% and 0.12% for respectively Zn, Cd, Ni, Pb and Cu, i.e. the degree of metal complexation in the river is the lowest for Zn and the highest for Cu. Metals in 1–300 nm particles were analyzed using Asymmetric Flow Field Flow Fractionation (AsF-FFF), but the overall recovery is quite low. The nano-sized Cu detected is mainly associated with DOM of 1–5 nm, whereas Pb and Zn are dominantly associated with particles of iron hydroxides and clay of larger size (30–100 nm). Free ion concentrations calculated with the speciation modeling are in good agreement with the measurements, except for Pb. Based on the model, DOM-bound is the most important complexed form for Cu and Cd, whereas formation of (bi)carbonate and EDTA complexes are more important for Ni and Zn. Adsorption of Pb to DOM is probably overestimated by the model, whereas Pb adsorption to iron hydroxides is underestimated.
    Genotoxic effects in the Eastern mudminnow (Umbra pygmaea) after prolonged exposure to River Rhine water, as assessed by use of the in vivo SCE and Comet assays
    Penders, E.J.M. ; Spenkelink, A. ; Hoogenboezem, W. ; Rotteveel, S.G.P. ; Maas, J.L. ; Alink, G.M. - \ 2012
    Environmental and Molecular Mutagenesis 53 (2012)4. - ISSN 0893-6692 - p. 304 - 310.
    surface waters - fish - exchanges - vitro
    The production of drinking water from river water requires a certain minimal river water quality. The Association of River Rhine Water Works (RIWA), therefore, operates a monitoring network. In vitro mutagenicity studies have shown that the genotoxicity of the River Rhine water steadily decreased from 1981 until 2001. Compared to a study in 1978, a decrease in genotoxicity was also observed in an in vivo genotoxicity study in 2005, in which Eastern mudminnows (Umbra pygmaea) were exposed to River Rhine water, and gill cells were used for the Sister Chromatid Exchange (SCE) test and the Comet assay. In this 2005 study, the in vivo genotoxicity increased upon extending exposure of the fish from 3 to 11 days. Therefore, the objectives of this study were to investigate (i) whether new data corroborate that in vivo genotoxicity of River Rhine water is at present lower than in 1978, (ii) whether the Comet assay is a suitable alternative to the SCE assay, and (iii) whether further prolonged exposure results in a further increase in in vivo genotoxicity. The new data corroborate that in vivo genotoxicity of River Rhine water is at present lower than in 1978. The Comet assay is a useful addition but does not provide a substitute for the SCE endpoint in these in vivo genotoxicity studies. Prolonging the exposure time of Eastern mudminnows to River Rhine water from 11 to 42 days did not give a significant increase in SCEs and DNA damage (Comet assay) in gill cells. Mol. Mutagen. 2012. (c) 2012 Wiley Periodicals, Inc.
    Transfer functions for solid solution partitioning of cadmium for Australian soils
    Vries, W. de; Mc Laughlin, M.J. ; Groenenberg, J.E. - \ 2011
    Environmental Pollution 159 (2011)12. - ISSN 0269-7491 - p. 3583 - 3594.
    metal-ion activities - contaminated soils - humic substances - organic-matter - heavy-metals - surface waters - fresh-waters - pore-water - copper - speciation
    To assess transport and ecotoxicological risks of metals, such as cadmium (Cd) in soils, models are needed for partitioning and speciation. We derived regression-based “partition-relations” based on adsorption and desorption experiments for main Australian soil types. First, batch adsorption experiments were carried out over a realistic range of dissolved Cd concentrations in agricultural soils in Australia. Results showed linear sorption relationships, implying the adequacy of using Kd values to describe partitioning. Desorption measurements were then carried out to assess in-situ Kd values and relate these to soil properties The best transfer functions for solid–solution partitioning were found for Kd values relating total dissolved Cd concentration to total soil Cd concentrations, accounting for the variation in pH, SOM contents and DOC concentrations. Model predictions compared well with measurements of an independent data set, but there was a tendency to underestimate dissolved Cd concentrations of highly polluted soils.
    Mapping cumulative environmental risks: examples from the EU NoMiracle project
    Pistocchi, A. ; Groenwold, J. ; Lahr, J. ; Loos, M. ; Mujica, M. ; Ragas, A.M.J. ; Rallo, R. ; Sala, S. ; Schlink, U. ; Strebel, K. ; Vighi, M. ; Vizcaino, P. - \ 2011
    Environmental Modeling and Assessment 16 (2011)2. - ISSN 1420-2026 - p. 119 - 133.
    self-organizing map - surface waters - pesticide mixtures - voc concentrations - independent action - exposure - indoor - contamination - validation - substances
    We present examples of cumulative chemical risk mapping methods developed within the NoMiracle project. The different examples illustrate the application of the concentration addition (CA) approach to pesticides at different scale, the integration in space of cumulative risks to individual organisms under the CA assumption, and two techniques to (1) integrate risks using data-driven, parametric statistical methods, and (2) cluster together areas with similar occurrence of different risk factors, respectively. The examples are used to discuss some general issues, particularly on the conventional nature of cumulative risk maps, and may provide some suggestions for the practice of cumulative risk mapping.
    Fate of hormones and pharmaceuticals during combined anaerobic treatment and nitrogen romoval by partial nitritation-anammox in vacuum collected black water
    Graaff, M.S. de; Vieno, N.M. ; Kujawa, K. ; Zeeman, G. ; Temmink, B.G. ; Buisman, C.J.N. - \ 2011
    Water Research 45 (2011)1. - ISSN 0043-1354 - p. 375 - 383.
    sewage-treatment plants - personal care products - waste-water - activated-sludge - aquatic environment - musk fragrances - surface waters - estrogens - antibiotics - behavior
    Vacuum collected black (toilet) water contains hormones and pharmaceuticals in relatively high concentrations (mu g/L to mg/L range) and separate specific treatment has the potential of minimizing their discharge to surface waters. In this study, the fate of estrogens (natural and synthetical hormones) and pharmaceuticals (paracetamol, metoprolol, propranolol, cetirizine, doxycycline, tetracycline, ciprofloxacin, trimethoprim, carbamazepine, ibuprofen and diclofenac) in the anaerobic treatment of vacuum collected black water followed by nitrogen removal by partial nitritation-anammox was investigated. A new analytical method was developed to detect the presence of several compounds in the complex matrix of concentrated black water. Detected concentrations in black water ranged from 1.1 mu g/L for carbamazepine to >1000 mu g/L for paracetamol. Anaerobic treatment was only suitable to remove the majority of paracetamol (>90%). Metoprolol was partly removed (67%) during aerobic treatment. Deconjugation could have affected the removal efficiency of ibuprofen as concentrations even increased during anaerobic treatment and only after the anammox treatment 77% of ibuprofen was removed. The presence of persistent micro-pollutants (diclofenac, carbamazepine and cetirizine), which are not susceptible for biodegradation, makes the application of advanced physical and chemical treatment unavoidable. (C) 2010 Elsevier Ltd. All rights reserved.
    Metribuzin impairs the unicell-colony transformation in the green alga Scenedesmus obliquus
    Lürling, M.F.L.L.W. - \ 2011
    Chemosphere 82 (2011)3. - ISSN 0045-6535 - p. 411 - 417.
    aquatic risk-assessment - comparative sensitivity - morphological defense - herbicide metribuzin - aliphatic sulfates - surface waters - phytoplankton - daphnia - growth - photosynthesis
    Active growth is a prerequisite for the formation of grazing-protective, mostly eight-celled colonies by the ubiquitous green alga Scenedesmus in response to chemical cues from zooplankton. Colonies can also be evoked by chemically quite similar manmade anionic surfactants, such as FFD-6. In this study, it was hypothesized that growth-inhibiting concentrations of the herbicide metribuzin impair the ability of Scenedesmus obliquus to form colonies in response to the surfactant morphogen FFD-6. The results confirmed that the formation of colonies in S. obliquus was hampered by metribuzin. EC50 values of metribuzin for colony inhibition (approximately 11 µg L-1) were similar to those for growth and photosynthesis inhibition (12–25 µg metribuzin L-1). In the absence of the colony-inducing surfactant FFD-6, S. obliquus populations were comprised of 92% unicells, having on average 1.2 cells per colony at all tested metribuzin concentrations (0–100 µg L-1). In contrast, in the presence of FFD-6 and at low metribuzin concentrations (0 and 5 µg L-1), S. obliquus had more than five cells per colony with a high portion of eight-celled colonies. However, increasing concentrations of metribuzin decreased the number of colonies in the FFD-6-exposed populations and caused them to remain mostly unicellular at the highest concentrations (50 and 100 µg L-1). This study revealed that metribuzin impeded growth and by doing so, also obstructed the possibility for unicellular Scenedesmus to form colonies. Consequently, an increase in mortality of Scenedesmus from grazing is expected.
    Calibration of Silicone Rubber Passive Samplers: Experimental and Modeled Relations between Sampling Rate and Compound Properties
    Rusina, T.P. ; Smedes, F. ; Koblizkova, M. ; Klanova, J. - \ 2010
    Environmental Science and Technology 44 (2010)1. - ISSN 0013-936X - p. 362 - 367.
    semipermeable-membrane devices - polycyclic aromatic-hydrocarbons - organic contaminants - uptake kinetics - hydrophobic chemicals - surface waters - spmds - coefficients - pollutants - partition
    Sampling rates (R-s) for silicone rubber (SR) passive samplers were measured under two different hydrodynamic conditions. Concentrations were maintained in the aqueous phase by continuous equilibration with SR sheets of a large total surface area which had been spiked with polycyclic aromatic hydrocarbons and/or polychlorinated biphenyls. Test sheets made of the same SR but of much smaller surface area were used to measure the uptake rate. Measured R-s values decreased with increasing passive sampler-water partition coefficient(K-pw) according to R-s approximate to K-pw(-0.08) under both hydrodynamic conditions. This decrease is not significantly different from modeled values if the uncertainty of the diffusion coefficients in water is included. Modeling also confirmed that uptake of the test compounds under the experimental conditions was entirely controlled by diffusion in the water phase. A model using R-s approximate to M-0.47 is suggested for extrapolation of R-s estimated from the dissipation of performance reference compounds to target compounds in a higher hydrophobicity range.
    Climate-dependent CO2 emissions from lakes
    Kosten, S. ; Roland, F. ; Motta Marques, D.M.L. Da; Nes, E.H. van; Mazzeo, N. ; Sternberg, L.S.L. ; Scheffer, M. ; Cole, J.J. - \ 2010
    Global Biogeochemical Cycles 24 (2010)2. - ISSN 0886-6236
    aquatic ecosystems - carbon-dioxide - metabolic balance - atmospheric co2 - surface waters - shallow lakes - boreal lakes - respiration - heterotrophy - terrestrial
    Inland waters, just as the world's oceans, play an important role in the global carbon cycle. While lakes and reservoirs typically emit CO2, they also bury carbon in their sediment. The net CO2 emission is largely the result of the decomposition or preservation of terrestrially supplied carbon. What regulates the balance between CO2 emission and carbon burial is not known, but climate change and temperature have been hypothesized to influence both processes. We analyzed patterns in carbon dioxide partial pressure (pCO2) in 83 shallow lakes over a large climatic gradient in South America and found a strong, positive correlation with temperature. The higher pCO2 in warmer lakes may be caused by a higher, temperature-dependent mineralization of organic carbon. This pattern suggests that cool lakes may start to emit more CO2 when they warm up because of climate cha
    Evaluation of approaches to calculate critical metal loads for forest soils
    Vries, W. de; Groenenberg, J.E. - \ 2009
    Environmental Pollution 157 (2009)12. - ISSN 0269-7491 - p. 3422 - 3432.
    biotic ligand model - scots pine-seedlings - organic-matter - humic substances - soil solution - kola-peninsula - surface waters - acute toxicity - air-pollution - fresh-waters
    This paper evaluates approaches to calculate acceptable loads for metal deposition to forest ecosystems, distinguishing between critical loads, stand-still loads and target loads. We also evaluated the influence of including the biochemical metal cycle on the calculated loads. Differences are illustrated by examples of Cd, Cu, Pb and Zn for a deciduous forest on five major soil types in the Netherlands. Stand-still loads are generally lower than critical loads, which in turn are lower than the target loads indicating that present levels are below critical levels. Uncertainties in the calculated critical loads are mainly determined by the uncertainty in the critical limits and the chemical speciation model. Including the metal cycle has a small effect on the calculated critical loads. Results are discussed in view of the applicability of the critical load concept for metals in future protocols on the reduction in metal emissions.
    Validation and application of a yeast bioassay for screening androgenic activity in calf urine and feed
    Bovee, T.F.H. ; Bor, G. ; Heskamp, H.H. ; Lasaroms, J.J.P. ; Sanders, M.B. ; Nielen, M.W.F. - \ 2009
    Analytica Chimica Acta 637 (2009)1-2. - ISSN 0003-2670 - p. 225 - 234.
    tandem mass-spectrometry - in-vitro - liquid-chromatography - estrogenic activity - recombinant assay - anabolic-steroids - receptor ligands - surface waters - binding - dihydrotestosterone
    Bioassays are valuable tools for combating the illegal use of steroids in cattle fattening. Previously we described the construction and properties of a rapid and robust yeast androgen bioassay stably expressing the human androgen receptor (hAR) and yeast enhanced green fluorescent protein (yEGFP), the latter in response to androgens. In the present study this yeast androgen bioassay was validated as a qualitative screening method for the determination of androgenic activity in calf urine and animal feed. This validation was performed according to EC Decision 2002/657. 20 blank samples were spiked with testosterone, 17¿-methyltestosterone, 19-nortestosterone, 17ß-trenbolone, 17ß-boldenone or 17¿-methylboldenone at 2 or 15 ng mL¿1 in urine and 50 or 100 ng g¿1 in feed. All blank and spiked samples fulfilled the CC¿ and CCß criterions, meaning that all 20 blank samples gave signals below the determined decision limits CC¿ and were thus classified as compliant (¿ = 1%). For each component, at least 19 out of the 20 spiked samples gave a signal above the CC¿ and were thus classified as suspect (ß = 5%). The method was specific, and high amounts of dexamethasone did not interfere with the outcome of the test. Although high levels of 17¿-ethynylestradiol can significantly inhibit the response obtained with low amounts of androgens, that situation is not relevant in veterinary practice. When stored at their specific conditions, the androgens in feed were stable for at least 91 days. Real urine samples from a national control program were screened and a representative part of the compliant and suspect samples were confirmed by gas chromatography¿tandem mass spectrometry
    Inter-laboratory comparison of a yeast bioassay for the determination of estrogenic activity in biological samples
    Bovee, T.F.H. ; Bor, G. ; Becue, I. ; Daamen, E.J. ; Duursen, M. van; Lehmann, S. ; Vollmer, G. ; Maria, R. De; Fox, E. ; Witters, H. ; Bernhoft, S. ; Schramm, K.W. ; Hoogenboom, L.A.P. ; Nielen, M.W.F. - \ 2009
    Analytica Chimica Acta 637 (2009)1-2. - ISSN 0003-2670 - p. 265 - 272.
    tandem mass-spectrometry - green fluorescent protein - liquid-chromatography - anabolic-steroids - recombinant assay - surface waters - beta-agonists - urine - validation - abuse
    An inter-laboratory exercise was performed with a yeast estrogen bioassay, based on the expression of yeast enhanced green fluorescent protein (yEGFP), for the determination of estrogenic activity in extracts of calf urine samples. Urine samples were spiked with 1 and 5 ng mL¿1 17ß-estradiol and 17¿-ethynylestradiol, 10 and 50 ng mL¿1 mestranol, and 100 ng mL¿1 testosterone and progesterone. Sample extracts of blank and spiked urine samples were prepared at our laboratory and sent to seven laboratories together with a reagent blank, a DMSO blank, and eight 17ß-estradiol stock solutions in DMSO ranging in concentration from 0 to 545 ng mL¿1. Sample extracts and standards were coded and tested blindly. A decision limit (CC¿) was determined based on the response of seven blank urine samples. Signals of the negative controls, e.g. urine samples spiked with 100 ng mL¿1 testosterone or progesterone, were all below the determined CC¿ and were thus screened as compliant. Positive controls, i.e. the urine samples spiked at two levels with 17ß-estradiol, 17¿-ethynylestradiol and mestranol, were almost all screened as suspect, i.e. gave signals above the determined CC¿. Determined EC50 values calculated from the 17ß-estradiol dose¿response curves obtained by the seven laboratories ranged from 0.59 to 0.95 nM
    Changes in ventilation and locomotion of Gammarus pulex (Crustacea, Amphipoda) in response to low concentrations of pharmaceuticals
    Lange, H.J. de; Peeters, E.T.H.M. ; Lürling, M.F.L.L.W. - \ 2009
    Human and Ecological Risk Assessment 15 (2009)1. - ISSN 1080-7039 - p. 111 - 120.
    sewage-treatment plants - fresh-water biomonitor - acid-mine drainage - behavioral-responses - impedance conversion - oncorhynchus-mykiss - surface waters - waste-water - toxicity - exposure
    Exposure to contaminants below lethal concentrations may affect the performance of organisms, resulting in measurable differences in behavior. We measured the response of the benthic invertebrate Gammarus pulex (Crustacea, Amphipoda) to sublethal concentrations of three pharmaceuticals, fluoxetine, ibuprofen and carbamazepine, and the cationic surfactant cetyltrimethylammonium bromide (CTAB). Responses in behavior during exposure were analyzed using the multivariate method of Principal Response Curves (PRC). The PRC results show that exposure to low pharmaceutical concentrations (range 1-100 ng/l) resulted in increased ventilation, whereas exposure to control or to high concentrations (1 ¿ g/l-1 mg/L) resulted in increased locomotion. Exposure to CTAB resulted in decreased locomotion and increased ventilation at increasing concentrations. The results of our experiments indicate that increased ventilation can be used as a general sign of stress, but not necessarily an early warning signal for mortality.
    Quantifying the effect of catchment land-use and water nutrient concentrations on freshwater river and stream biodiversity
    Weijters, M.J. ; Janse, J.H. ; Alkemade, J.R.M. ; Verhoeven, J.T.A. - \ 2009
    Aquatic conservation: marine and freshwater ecosystems 19 (2009)1. - ISSN 1052-7613 - p. 104 - 112.
    multiple spatial scales - biotic integrity - new-zealand - community structure - nonpoint pollution - fish communities - surface waters - north-carolina - phosphorus - impacts
    A major threat to freshwater taxon diversity is the alteration of natural catchment Land use into agriculture, industry or urban areas and the associated eutrophication of the water. In order to stop freshwater biodiversity loss, it is essential to quantify the relationships between freshwater diversity and catchment Land use and water nutrient concentrations. 2. A literature survey was carried out on biodiversity data from rivers and streams. Fish and macroinvertebrates were selected as focal groups as they are widely used as indicator species of river and stream health. Only published data were selected that (a) compared data found at impaired sites with a pristine reference situation (either in time or space), (b) clearly defined the stressors studied (Land use cover and/or nutrient concentrations), and (c) clearly defined biodiversity (number of native species, species lists or IBI-scores). 3. The number of native taxa found in each study was transferred in an index of relative taxon richness (RTR) ranging from 0 (severely altered) to 100 (pristine reference conditions). Only those taxa were included that were (at least) present in the most pristine situation. This made it possible to combine, compare and analyse results from different studies. Catchment Land use was expressed as the percentage of non-natural Land use (agriculture, industry, housing or mining). As a measure of nutrients, the concentrations of NO3, NH4, PO4, total N and total P in the river and stream water were used. 4. Over 240 published articles have been studied, but only 22 met the criteria described above and could be used for further analysis. 5. This study showed that altered catchment Land use has a major effect on freshwater biodiversity and that the rate of species loss is serious; on average every 10% of lost natural catchment Land use cover leads to a loss of almost 6% (±0.83) of the native freshwater fish and macroinvertebrate species.
    Groundwater chemistry of Al under Dutch acid sandy soils: effects of land use and depth.
    Fest, E. ; Temminghoff, E.J.M. ; Griffioen, J. ; Grift, B. ; Riemsdijk, W.H. van - \ 2007
    Applied Geochemistry 22 (2007)7. - ISSN 0883-2927 - p. 1427 - 1438.
    dissolved organic-matter - acid forest soils - aluminum solubility - bs horizons - unsaturated zone - natural-waters - surface waters - heavy-metals - nica-donnan - speciation
    Aluminium has received great attention in the second half of the 20th century, mainly in the context of the acid rain problem mostly in forest soils. In this research the effect of land use and depth of the groundwater on Al, pH and DOC concentration in groundwater under Dutch sandy soils has been studied. Both pH and DOC concentration play a major role in the speciation of Al in solution. Furthermore, the equilibrium with mineral phases like gibbsite, amorphous Al(OH)3 and imogolite, has been considered. Agricultural and natural land use were expected to have different effects on the pH and DOC concentration, which in turn could influence the total Al concentration and the speciation of Al in groundwater at different depths (phreatic, shallow and deep). An extensive dataset (n = 2181) from the national and some provincial monitoring networks on soil and groundwater quality was used. Land use type and groundwater depth did influence the pH, and Al and DOC concentrations in groundwater samples. The Al concentration ranged from 7 to 1941 ¿mol L¿1 at pH <4; highest Al concentrations were found for natural-phreatic groundwater. The DOC concentration decreased and the median pH increased with depth of the groundwater. Natural-phreatic groundwater showed lower pH than the agricultural-phreatic groundwater. Highest DOC concentrations were found for the agricultural-phreatic groundwater, induced by the application of organic fertilizers. Besides inorganic complexation, the NICA-Donnan model was used to calculate Al3+ concentrations for complexation with DOC. Below pH 4.5 groundwater samples were mainly in disequilibrium with a mineral phase. This disequilibrium is considered to be the result of kinetic constraints or equilibrium with organic matter. Log K values were derived by linear regression and were close to theoretical values for Al(OH)3 minerals (e.g. gibbsite or amorphous Al(OH)3), except for natural-phreatic groundwater for which lower log K values were found. Complexation of Al with DOC is shown to be an important factor for the Al concentrations, especially at high DOC concentrations as was found for agricultural-phreatic groundwater.
    Impact of soil properties on critical concentrations of cadmium, lead, copper, zinc and mercury in soil and soil solution in view of ecotoxicological effects
    Vries, W. de; Lofts, S. ; Tipping, E. ; Meili, M. ; Groenenberg, J.E. ; Schutze, G. - \ 2007
    Reviews of Environmental Contamination and Toxicology 191 (2007). - ISSN 0179-5953 - p. 47 - 89.
    biotic ligand model - species-sensitivity distributions - dissolved organic-matter - contaminated soils - humic substances - heavy-metals - microbial processes - surface waters - acute toxicity - fresh-waters
    Concern about the input of metals to terrestrial ecosystems is related to (i) the ecotoxicological impact on soil organisms and plants (Bringmark et al. 1998; Palmborg et al. 1998) and also on aquatic organisms resulting from runoff to surface water and (ii) the uptake via food chains into animal tissues and products, which may result in health effects on animals and humans (Clark 1989). Effects on soil organisms, including microorganisms/macrofungi and soil fauna, such as nematodes and earthworms, are reduced species diversity, abundance, and biomass and changes in microbe-mediated processes (Bengtsson and Tranvik 1989; Giller et al. 1998; Vig et al. 2003). Effects on vascular plants include reduced development and growth of roots and shoots, elevated concentrations of starch and total sugar, decreased nutrient contents in foliar tissues, and decreased enzymatic activity (Prasad 1995; Das et al. 1997). A review of these phytotoxic effects is given by Balsberg-Påhlsson (1989). Effects on aquatic organisms, including algae, Crustacea, and fish, include effects on gill function (Sola et al. 1995), nervous systems (Baatrup 1991), and growth and reproduction rates (Mance 1987). Environmental quality standards or critical limits, often also denoted as Predicted No Effect Concentrations, or PNECs, for metals in soils and surface waters related to those effects serve as a guide in the environmental risk assessment process for those substances.
    Reduced nitrate concentrations in shallow ground water under a non-fertilised grass buffer strip.
    Beek, C.L. ; Heinen, M. ; Clevering, O.A. - \ 2007
    Nutrient Cycling in Agroecosystems 79 (2007)1. - ISSN 1385-1314 - p. 81 - 91.
    nitrogen removal - surface waters - coastal-plain - riparian zone - sandy soil - dynamics - agriculture - netherlands - movement - quality
    In this paper the suitability of a buffer strip to reduce nitrate concentrations in the upper groundwater was tested for a sandy arable soil in The Netherlands during two consecutive leaching seasons. The bufferstrip was a 3.5 m wide unfertilised grass strip adjacent to a ditch on an arable field. In total 24 groundwater wells were installed in 4 transects perpendicular to the ditch to determine Cl, NO3 and ¿15N concentrations. Piezometers were installed to assess the groundwater flow, which was in the direction of the ditch with small downward leakage across a peat layer at about 3 m depth. Nitrogen was dominantly present as nitrate (NO3). The NO3-N concentrations under the bufferstrip were significantly lower than under the adjacent arable field. The lower concentrations were due to dilution, uptake by grass and denitrification. Nitrate was actively removed in the bufferstrip, since the Cl/NO3 ratios were higher in the bufferstrip than in the remainder of the field. Furthermore, ¿15N data indicated that denitrification occurred in the groundwater and increased with decreasing distance to the ditch. NO3-N loads to the ditch were estimated at 8.5 kg ha¿1yr¿1, which is relatively low for this area. We can, however, not determine whether these relatively low NO3-N loads were causally related to the reduced NO3-N concentrations in the bufferstrip. Nevertheless, the results of the present study are promising and justify additional research on the efficiency of bufferstrips to reduce NO3 concentrations in shallow groundwater, and subsequently reduce NO3 loading of surface water, under Dutch conditions
    A new highly specific and robust yeast androgen bioassay for the detection of agonist and antagonists
    Bovee, T.F.H. ; Helsdingen, J.R. ; Hamers, A.R.M. ; Duursen, M. van; Nielen, M.W.F. ; Hoogenboom, L.A.P. - \ 2007
    Analytical and Bioanalytical Chemistry 389 (2007)5. - ISSN 1618-2642 - p. 1549 - 1558.
    green fluorescent protein - in-vitro - estrogenic activity - recombinant assay - response element - receptor-binding - surface waters - transcription - progesterone - validation
    Public concern about the presence of natural and anthropogenic compounds which affect human health by modulating normal endocrine functions is continuously growing. Fast and simple high-throughput screening methods for the detection of hormone activities are thus indispensable. During the last two decades, a panel of different in vitro assays has been developed, mainly for compounds with an estrogenic mode of action. Here we describe the development of an androgen transcription activation assay that is easy to use in routine screening. Recombinant yeast cells were constructed that express the human androgen receptor and yeast enhanced green fluorescent protein (yEGFP), the latter in response to androgens. Compared with other reporters, the yEGFP reporter protein is very convenient because it is directly measurable in intact living cells, i.e., cell wall disruption and the addition of a substrate are not needed. When yeast was exposed to 17 beta-testosterone, the concentration where half-maximal activation is reached (EC50) was 50 nM. The relative androgenic potencies, defined as the ratio between the EC50 of 17 beta-testosterone and the EC50 of the compound, of 5 alpha-dihydrotestosterone, methyltrienolone, and 17 beta-boldenone are 2.3, 1.4, and 0.15 respectively. The results presented in this paper demonstrate that this new yeast androgen bioassay is fast, sensitive, and very specific and also suited to detect compounds that have an antiandrogenic mode of action.
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