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1.
Plant communities in relation to flooding and soil contamination in a lowland Rhine River floodplain
Schipper AM Lotterman K Leuven RS Ragas AM de Kroon H Hendriks AJ 《Environmental pollution (Barking, Essex : 1987)》2011,159(1):182-189
Using canonical correspondence analysis (CCA), relationships were investigated between plant species composition and flooding characteristics, heavy metal contamination and soil properties in a lowland floodplain of the Rhine River. Floodplain elevation and yearly average flooding duration turned out to be more important for explaining variation in plant species composition than soil heavy metal contamination. Nevertheless, plant species richness and diversity showed a significant decrease with the level of contamination. As single heavy metal concentrations seemed mostly too low for causing phytotoxic effects in plants, this trend is possibly explained by additive effects of multiple contaminants or by the concomitant influences of contamination and non-chemical stressors like flooding. These results suggest that impacts of soil contamination on plants in floodplains could be larger than expected from mere soil concentrations. In general, these findings emphasize the relevance of analyzing effects of toxic substances in concert with the effects of other relevant stressors. 相似文献
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Flores N. Y. Collas F. P. L. Mehler K. Schoor M. M. Feld C. K. Leuven R. S. E. W. 《Environmental Modeling and Assessment》2022,27(1):187-204
Environmental Modeling & Assessment - Longitudinal training dams (LTDs) in the river Waal are novel river training structures that protect the littoral zone from the adverse effects of... 相似文献
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S. Wijnhoven G. Van Der Velde R. S. E. W. Leuven H. J. P. Eijsackers A. J. M. Smits 《Chemistry and Ecology》2013,29(6):463-477
Ecotoxicological risks of sediment contamination in floodplains are supposed to be highest in the regularly flooded parts. Therefore, in risk assessments, the non-flooded parts are neglected or considered to be reference areas. We investigated the metal extractability and levels in important food sources for vertebrates, viz. grass shoots and earthworms, in flooded as well as non-flooded parts and compared these with total metal concentrations. A comparison of these areas in the moderately polluted ‘Afferdensche en Deestsche Waarden’ floodplains along the River Rhine showed that total Zn, Pb, and Cd concentrations were highest in the regularly flooded parts. However, CaCl2-extractable Zn concentrations were highest in non-flooded areas, and those of Pb and Cd were equal in both areas. Total Cu concentrations were not significantly different between the two areas, but CaCl2-extractable Cu concentrations were highest in the regularly flooded areas. The metal concentrations in grass shoots of non-flooded areas were equal to (Zn, Cu, Cd) or higher than (Pb) those in regularly flooded areas. Zn concentrations in earthworms in regularly flooded areas were higher, but concentrations of Cu, Pb, and Cd were not. Ecotoxicological risk assessments require analysis of the total and potentially bioavailable metal concentrations in soils as well as concentrations in biota. This study shows that the less contaminated non-flooded areas in moderately polluted floodplains cannot be neglected in metal accumulation studies and cannot be used as pristine reference areas. 相似文献
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Mussels () were exposed to di-2-ethylhexyl phthalate (DEHP) and to di-isodecyl phthalate (DIDP) over a period of 28 days. The bioconcentration factor (BCF) as measured by 14C analysis, reached estimated plateau levels corresponding to mean BCF values of approximately 2500 and 3500 for the DEHP and DIDP respectively. The mussels were then held in clean seawater for a further 14 days and 14C analysis showed a depuration half-life of approximately 3.5 days for both phthalates. During the whole 42 days of the experiment general observations on the health of the animals showed no evidence of any adverse effects. 相似文献
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S. Wijnhoven G. Van Der Velde R. S. E. W. Leuven H. J. P. Eijsackers A. J. M. Smits 《Chemistry and Ecology》2006,22(6):463-477
Ecotoxicological risks of sediment contamination in floodplains are supposed to be highest in the regularly flooded parts. Therefore, in risk assessments, the non-flooded parts are neglected or considered to be reference areas. We investigated the metal extractability and levels in important food sources for vertebrates, viz. grass shoots and earthworms, in flooded as well as non-flooded parts and compared these with total metal concentrations. A comparison of these areas in the moderately polluted 'Afferdensche en Deestsche Waarden' floodplains along the River Rhine showed that total Zn, Pb, and Cd concentrations were highest in the regularly flooded parts. However, CaCl2-extractable Zn concentrations were highest in non-flooded areas, and those of Pb and Cd were equal in both areas. Total Cu concentrations were not significantly different between the two areas, but CaCl2-extractable Cu concentrations were highest in the regularly flooded areas. The metal concentrations in grass shoots of non-flooded areas were equal to (Zn, Cu, Cd) or higher than (Pb) those in regularly flooded areas. Zn concentrations in earthworms in regularly flooded areas were higher, but concentrations of Cu, Pb, and Cd were not. Ecotoxicological risk assessments require analysis of the total and potentially bioavailable metal concentrations in soils as well as concentrations in biota. This study shows that the less contaminated non-flooded areas in moderately polluted floodplains cannot be neglected in metal accumulation studies and cannot be used as pristine reference areas. 相似文献
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Schipper AM Wijnhoven S Leuven RS Ragas AM Hendriks AJ 《Environmental pollution (Barking, Essex : 1987)》2008,151(1):17-26
Soil metal concentrations, inundation characteristics and abundances of 14 arthropod taxa were investigated in a moderately contaminated lowland floodplain along the Rhine River and compared to the hinterland. Internal metal concentrations were determined for the orders of Coleoptera (beetles) and Araneida (spiders) and were related to soil concentrations. The floodplain was characterized by larger arthropod abundance than the hinterland, in spite of recurrent inundations and higher soil metal concentrations. Most arthropod taxa showed increasing abundance with decreasing distance to the river channel and increasing average inundation duration. For Cd, Cu, Pb and Zn, significant relations were found between arthropod concentrations and concentrations in soil. Significant relations were few but positive, indicating that increasing soil concentrations result in increasing body burdens in arthropods. For arthropod-eating vertebrates, these results might imply that larger prey availability in the floodplain coincides with higher metal concentrations in prey, possibly leading to increased exposure to metal contamination. 相似文献
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As a member of the British Oxford Group, psychologist Richard Ryder marked the beginning of the modern animal rights and animal welfare movement in the seventies. By introducing the concept “speciesism.” Ryder contributed importantly to the expansion of this movement. Surprisingly little attention has been paid to Ryder’s moral theory, “painism”, that aims to resolve the conflict between the two predominant rival theories in animal ethics, the deontological of Tom Regan and the utilitarian of Peter Singer. First, this paper examines the kernel and historical sources of Ryder’s painist theory, linking it to the work of John Rawls and Jean-Jacques Rousseau. Second, it examines Ryder’s critique of utilitarianism. It is argued that his critique of Singer’s use of the word “sentience” is unconvincing and that his critique of utilitarian aggregation as not taking a full account of the metaphysical separateness of persons, has already been countered and dealt with. Finally this paper looks at some of the counterintuitive implications of Ryder’s theory and argues that utilitarianism might have more resources for dealing with its own alleged counterintuitive implications than Ryder acknowledges. 相似文献
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Wijnhoven S van der Velde G Leuven RS Eijsackers HJ Smits AJ 《Environmental pollution (Barking, Essex : 1987)》2006,140(3):444-452
Turbation is hypothesized to affect the redistribution of heavy metals in polluted floodplain soils by effects on mobility. This hypothesis was tested in microcosms by turbation of zinc-spiked sediment top layers. Manual turbation caused a fast decrease of the zinc content in the upper 15 cm of the soil, even though turbation was only applied to the upper two centimetres. It was especially zinc attached to colloid and organic matter particles that was redistributed from the top layer. Percolation processes resulted in the attached zinc being drained to depths of more than 15 cm. The decrease in zinc content of the topsoil was even stronger in combination with inundation. No indications were found for the redistribution of zinc as a result of an increase of the extractability with 0.01 M CaCl2 or changes in pH. The findings suggest that mechanical turbation and bioturbation may redistribute heavy metals from topsoils in polluted floodplains just after inundation as observed in these turbation experiments. 相似文献
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A procedure for incorporating spatial variability in ecological risk assessment of Dutch river floodplains 总被引:9,自引:0,他引:9
Floodplain soils along the river Rhine in the Netherlands show a large spatial variability in pollutant concentrations. For
an accurate ecological risk characterization of the river floodplains, this heterogeneity has to be included into the ecological
risk assessment. In this paper a procedure is presented that incorporates spatial components of exposure into the risk assessment
by linking geographical information systems (GIS) with models that estimate exposure for the most sensitive species of a floodplain.
The procedure uses readily available site-specific data and is applicable to a wide range of locations and floodplain management
scenarios. The procedure is applied to estimate exposure risks to metals for a typical foodweb in the Afferdensche and Deestsche
Waarden floodplain along the river Waal, the main branch of the Rhine in the Netherlands. Spatial variability of pollutants
is quantified by overlaying appropriate topographic and soil maps resulting in the definition of homogeneous pollution units.
Next to that, GIS is used to include foraging behavior of the exposed terrestrial organisms. Risk estimates from a probabilistic
exposure model were used to construct site-specific risk maps for the floodplain. Based on these maps, recommendations for
future management of the floodplain can be made that aim at both ecological rehabilitation and an optimal flood defense. 相似文献