Eight potentially toxic trace elements were investigated together with the physicochemical characteristics of sediments collected upstream, downstream, and from various ponds from three adjacent carbonated agricultural catchments in southwestern France. Geochemical indices with local references and multivariate data analysis revealed a significant enrichment of Cd, followed by Ni and Cu in sediments, originating from agricultural practices, especially in the upper catchments sensitive to erosion processes. Five other PTEs (As, Pb, Co, Cr, and Zn) mostly originated from the weathering process of the molasse. Clay minerals and/or iron oxides were the main controlling factors for most PTEs. In ponds, Cd was regulated by Ca co-precipitation favoured by the long hydraulic retention time and increased pH, whereas it was mostly controlled by silicates in stream sediments. Copper, Pb, and Cd were the highly extractable metals, suggesting the risk of a hazardous environment. Multivariate analysis revealed that several environmental factors affected the spatial variation of PTE concentrations in sediments as well as the trapping role of ponds (texture, slope, soil erosion, pond size and position, discharge, hydraulic retention time) in this area of intensive agricultural practices. Our conclusions are useful for pond management in a context of increasing water demand and climate warming.

研究人员调查了八个潜在有毒的微量元素，以及从法国西南部三个相邻的碳酸盐农业流域上游，下游和从各个池塘收集的沉积物的理化特性。结合当地参考资料和多变量数据分析的地球化学指标显示，镉的含量显着增加，其次是沉积物中的镍和铜，其源于农业实践，尤其是对侵蚀过程敏感的上游流域。其他五个PTE（As，Pb，Co，Cr和Zn）主要来自糖蜜的风化过程。粘土矿物和/或氧化铁是大多数PTE的主要控制因素。在池塘中，镉通过钙共沉淀来调节，而钙的共沉淀有利于延长水力停留时间和增加pH值，而它主要受河流沉积物中的硅酸盐控制。铜，铅和镉是高度可萃取的金属，表明存在危险环境的风险。多变量分析表明，在该集约化农业实践领域中，一些环境因素影响了沉积物中PTE浓度的空间变化以及池塘的诱捕作用（纹理，坡度，土壤侵蚀，池塘大小和位置，流量，水力滞留时间）。 。在水需求增加和气候变暖的背景下，我们的结论对池塘管理很有用。多变量分析表明，在该集约化农业实践领域中，一些环境因素影响了沉积物中PTE浓度的空间变化以及池塘的诱捕作用（纹理，坡度，土壤侵蚀，池塘大小和位置，流量，水力滞留时间）。 。在水需求增加和气候变暖的背景下，我们的结论对池塘管理很有用。多变量分析表明，在该集约化农业实践领域中，一些环境因素影响了沉积物中PTE浓度的空间变化以及池塘的诱捕作用（纹理，坡度，土壤侵蚀，池塘大小和位置，流量，水力滞留时间）。 。在水需求增加和气候变暖的背景下，我们的结论对池塘管理很有用。