Wiley, Environmental Toxicology and Chemistry, 4(27), p. 919
DOI: 10.1897/07-252.1
Wiley, Environmental Toxicology and Chemistry, 2008(preprint), p. 1
DOI: 10.1897/07-252
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To analyze the influence of environmental heterogeneity on heavy metal exposure concentrations for terrestrial vertebrates in river floodplains, a spatially explicit exposure model has been constructed (SpaCE-model: Spatially explicit Cumulative Exposure model). This model simulates the environmental use of individual organisms by selecting model cells to be foraged in within a multi-celled heterogeneous landscape. Exposure duration and exposure concentrations are calculated along the selected cells, whereby exposure concentrations are dependent on the availability and contaminant concentrations of different diet items in each cell. The model was applied to a selection of 10 terrestrial vertebrate species, including six small mammal and four top predator species. It was parameterized for cadmium contamination in a 285 ha embanked floodplain area along the Rhine River in The Netherlands. Simulations of 1000 individuals for each species resulted in intra-species variation in exposure concentrations between 11 and 39 %, the smallest values generally corresponding to the species with the largest home ranges. Comparison of the model results with cadmium concentrations measured in four of the species from the study area showed that the predicted variation accounts for 12 to 16 % of the variation in the measurements. This indicates that environmental heterogeneity governs a minor part of the variation in metal exposure concentrations that can actually be observed in river floodplains. ; To analyze the influence of environmental heterogeneity on heavy metal exposure concentrations for terrestrial vertebrates in river floodplains, a spatially explicit exposure model has been constructed (SpaCE-model: Spatially explicit Cumulative Exposure model). This model simulates the environmental use of individual organisms by selecting model cells to be foraged in within a multi-celled heterogeneous landscape. Exposure duration and exposure concentrations are calculated along the selected cells, whereby exposure concentrations are dependent on the availability and contaminant concentrations of different diet items in each cell. The model was applied to a selection of 10 terrestrial vertebrate species, including six small mammal and four top predator species. It was parameterized for cadmium contamination in a 285 ha embanked floodplain area along the Rhine River in The Netherlands. Simulations of 1000 individuals for each species resulted in intra-species variation in exposure concentrations between 11 and 39 %, the smallest values generally corresponding to the species with the largest home ranges. Comparison of the model results with cadmium concentrations measured in four of the species from the study area showed that the predicted variation accounts for 12 to 16 % of the variation in the measurements. This indicates that environmental heterogeneity governs a minor part of the variation in metal exposure concentrations that can actually be observed in river floodplains.