iES Landau, Institute for Environmental Sciences, University Koblenz-Landau, Fortstraße 7, 76829 Landau in der Pfalz, Germany.
iES Landau, Institute for Environmental Sciences, University Koblenz-Landau, Fortstraße 7, 76829 Landau in der Pfalz, Germany.
Sci Total Environ. 2022 Jul 1;828:154549. doi: 10.1016/j.scitotenv.2022.154549. Epub 2022 Mar 14.
Traditional forms of agriculture have created and preserved heterogeneous landscapes characterized by semi-natural meadows and pastures, which have high conversation value for biodiversity. Landscapes in Central and Eastern European countries with traditional agriculture are a stronghold for pollinators, butterflies and amphibians, which have declined in other parts of Europe. Despite different landscape structures, agriculture-associated pesticide exposure in streams can be similarly high as in Western Europe. This raises the question whether the heterogeneous landscape can buffer a temporary water quality decline by agriculture. We investigated the influence of landscape heterogeneity and water quality, in particular pesticide exposure, on macroinvertebrate communities in 19 small streams in Central Romania. We sampled the macroinvertebrate community, assessed the ecosystem function of leaf litter decomposition and analyzed the parasite prevalence in Baetis sp. and Gammarus balcanicus. No association between pesticide toxicity towards macroinvertebrates and several macroinvertebrate metrics was found. However, the level of pesticide toxicity was generally high, constituting a rather short gradient, and the pesticide indicator SPEAR implied pesticide-driven community change in all sites. Landscape heterogeneity and forested upstream sections were among the most important drivers for the macroinvertebrate metrics, indicating increased dispersal and recolonization success. Agricultural land use in the catchment was negatively associated with vulnerable macroinvertebrate taxa such as Ephemeroptera, Plecoptera and Trichoptera. G. balcanicus dominated the shredder taxa and its abundance was positively associated with the pesticide indicator SPEAR. Parasite prevalence in G. balcanicus increased with extensive land use (pastures and forests), whereas it decreased with arable land. Our results suggest that heterogeneous landscapes with structures of low-intensive land use may buffer the effects of agricultural land use and facilitate dispersal and recolonization processes of pesticide-affected macroinvertebrate communities.
传统农业形式创造和保护了具有半自然草地和牧场的异质景观，这些景观对生物多样性具有高保护价值。具有传统农业的中东欧国家的景观是传粉媒介、蝴蝶和两栖动物的据点，而这些在欧洲其他地区的数量却有所减少。尽管景观结构不同，但与农业相关的溪流农药暴露在某些方面与西欧相似。这就提出了一个问题，即异质景观是否可以缓冲农业造成的水质暂时下降。我们研究了景观异质性和水质（特别是农药暴露）对罗马尼亚中部 19 条小溪中的大型底栖无脊椎动物群落的影响。我们对大型底栖无脊椎动物群落进行了采样，评估了叶片分解的生态系统功能，并分析了 Baetis sp. 和 Gammarus balcanicus 中的寄生虫流行率。我们没有发现农药对大型底栖无脊椎动物的毒性与几个大型底栖无脊椎动物指标之间存在关联。然而，农药毒性水平普遍较高，构成了一个相当短的梯度，而且农药指示物 SPEAR 表明所有地点的农药驱动的群落变化。景观异质性和上游的森林区是大型底栖无脊椎动物指标的最重要驱动因素之一，表明扩散和再定居成功率增加。流域内的农业用地与脆弱的大型底栖无脊椎动物类群（如蜉蝣目、石蝇目和毛翅目）呈负相关。G. balcanicus 主导着撕食者类群，其丰度与农药指示物 SPEAR 呈正相关。G. balcanicus 的寄生虫流行率随着广泛的土地利用（牧场和森林）而增加，而随着耕地的增加而减少。我们的结果表明，具有低强度土地利用结构的异质景观可能缓冲农业用地利用的影响，并促进受农药影响的大型底栖无脊椎动物群落的扩散和再定居过程。
