Saarland University, Physical Geography and Environmental Research, Am Markt Zeile 2, D-66125 Saarbrücken, Germany.
Saarland University, Physical Geography and Environmental Research, Am Markt Zeile 2, D-66125 Saarbrücken, Germany.
Sci Total Environ. 2018 Apr 1;619-620:638-648. doi: 10.1016/j.scitotenv.2017.11.155. Epub 2017 Nov 29.
Pesticides are a major burden for stream ecosystems in the central European cultivated landscape. The objective of the present study was to investigate the applicability of ecological indicator methods in relation to toxicity of pesticides under the specific hydro-morphological conditions in small water bodies. Thus, an association of toxicity evaluating methods with different ecological indicators was to be attempted. Based on three random samples taken within the 2016 vegetation period, 23 headwater areas in the Saarland were investigated to test for pesticides and their metabolites. The macroinvertebrate population was also surveyed in 16 of these streams. Evidence was found of 41 substances in total. Most dominant substances include atrazine, isoproturone, quinmerac and tebuconazol as well as metabolites of dimethenamid, chloridazon and metazachlor. At 9 of the 23 sampling points, over 10 plant protection products and metabolites were found. Only 17% of the water bodies investigated contained fewer than 5 substances. Around half of the bodies of water investigated show noticeably high concentrations of metabolites of plant protection products. Maximum concentrations exceeding environmental quality standards or the Health-oriented Guideline Values were measured for 13 substances at individual sampling points. Analysis of the biological data for only 4 of the water bodies investigated resulted in the Ecological Status Class (ESC) "good". All others fell short of the quality target, although they were classified as "good" or "very good" according to the Saprobic index. SPEAR as a measurement of the sensitivity of the biocoenosis to pesticides shows their influence in a few water bodies. Likewise, high toxic unit values have also been calculated, indicating the presence of toxic substances at relevant concentrations. However, an actual correlation between SPEAR and toxic unit could not be derived. Clearly in these very headwater streams other habitat-determining hydromorphological factors overlay the toxic impact of pesticides.
农药是中欧耕作景观中溪流生态系统的主要负担。本研究的目的是调查生态指标方法在小水体特定水-形态条件下与农药毒性的相关性。因此，试图将毒性评估方法与不同的生态指标联系起来。根据 2016 年植被期内的三个随机样本，对萨尔州的 23 个源头区进行了调查，以检测农药及其代谢物。其中 16 条溪流还调查了大型底栖无脊椎动物种群。总共发现了 41 种物质。最主要的物质包括莠去津、异丙隆、苯氧喹啉和戊唑醇以及二甲吩草胺、氯嘧磺隆和甲嗪草酮的代谢物。在 23 个采样点中的 9 个点，发现了超过 10 种植保产品和代谢物。只有 17%的调查水体中含有少于 5 种物质。大约一半的调查水体显示出明显高浓度的植保产品代谢物。在个别采样点，有 13 种物质的最大浓度超过了环境质量标准或健康导向指导值。对仅 4 个调查水体的生物数据进行分析，结果得出生态状况等级（ESC）为“良好”。其他所有水体都未达到质量目标，尽管根据 saprobic 指数，它们被归类为“良好”或“非常好”。作为生物群落对农药敏感性的测量，SPEAR 显示了它们在少数水体中的影响。同样，也计算出了高毒性单位值，表明存在具有相关浓度的有毒物质。然而，并没有得出 SPEAR 和毒性单位之间的实际相关性。显然，在这些非常小的溪流中，其他决定栖息地的水-形态因素掩盖了农药的毒性影响。
