Effects of pesticides on community structure and ecosystem functions in agricultural streams of three biogeographical regions in Europe. Sci Total Environ

UFZ - Helmholtz Centre for Environmental Research, Dept. System Ecotoxicology, Permoser Strasse 15, 04318 Leipzig, Germany.
Science of The Total Environment (Impact Factor: 4.1). 10/2007; 382(2-3):272-85. DOI: 10.1016/j.scitotenv.2007.04.040
Source: PubMed


There is a paucity of large-scale field investigations on the effects of organic toxicants on stream macroinvertebrate community structure and ecosystem functions. We investigated a total of 29 streams in two study areas of France and Finland for pesticide exposure, invertebrates and leaf-litter breakdown. To link pesticide exposure and community composition we applied the trait-based Species At Risk (SPEAR) indicator system. In the French region, pesticide stress was associated with a decrease in the relative abundance and number of sensitive species in the communities. The presence of undisturbed upstream reaches partly compensated the effects of pesticide contamination. Functional effects of pesticides were identified by a 2.5-fold reduction of the leaf-litter breakdown rate that was closely correlated with the structural changes in the contaminated streams. No effects of pesticides were observed in Finnish streams since contamination with pesticides was very low. In a follow-up analysis, the SPEAR approach successfully discriminated between reference and contaminated sites across different biogeographical regions, also including results of a previous field study in North Germany. Furthermore, change of the community structure was detectable at a concentration range as low as 1/100 to 1/1000 the acute 48 h-LC50 of Daphnia magna. Our findings demonstrate that pesticides may influence the structure and function of lotic ecosystems and that the SPEAR approach can be used as a powerful tool in biomonitoring over large spatial scales.

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Available from: Matthias Liess, Mar 05, 2014
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    • "Dijksterhuis et al. 2011; Maltby et al. 2009). Accordingly, Schäfer et al. (2007; 2011) and Rasmussen et al. (2012b) detected an up to 4-fold reduction in microbial OMD in agriculturally-impacted streams compared to reference sites. Pesticide toxicity towards microorganisms was identified as the most influential predictor of OMD. "
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    Bulletin of Environmental Contamination and Toxicology 09/2015; DOI:10.1007/s00128-015-1642-1 · 1.26 Impact Factor
    • "Young, Matthaei & Townsend, 2008) could be incorporated to capture the extent of impacts and recovery trajectories more fully. Although covering only part of the spectrum of responses reported here, other multimetric bioassessments have yielded comparable results, including how pesticides can indirectly release prey species from predation (Papst & Boyer, 1980), constrain consumer populations through loss of resources (Brazner & Kline, 1990), affect the structure and functioning of aquatic communities in mesocosms (Downing et al., 2008; Relyea, 2008; Halstead et al., 2014) or alter the structure and functioning of natural stream communities (Chung et al., 1993; Sch€ afer et al., 2007). Results from correlational studies also suggest that changes at multiple trophic levels may be related to organic chemical contaminants (mostly pesticides ) at the continental scale (Malaj et al., 2014). "
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