Plant-Soil-Interactions, Agroscope, Zurich, Switzerland.
Department of Plant and Microbial Biology, University of Zurich, Zurich, Switzerland.
Environ Sci Technol. 2021 Mar 2;55(5):2919-2928. doi: 10.1021/acs.est.0c06405. Epub 2021 Feb 3.
Pesticides are applied in large quantities to agroecosystems worldwide. To date, few studies assessed the occurrence of pesticides in organically managed agricultural soils, and it is unresolved whether these pesticide residues affect soil life. We screened 100 fields under organic and conventional management with an analytical method containing 46 pesticides (16 herbicides, 8 herbicide transformation products, 17 fungicides, seven insecticides). Pesticides were found in all sites, including 40 organic fields. The number of pesticide residues was two times and the concentration nine times higher in conventional compared to organic fields. Pesticide number and concentrations significantly decreased with the duration of organic management. Even after 20 years of organic agriculture, up to 16 different pesticide residues were present. Microbial biomass and specifically the abundance of arbuscular mycorrhizal fungi, a widespread group of beneficial plant symbionts, were significantly negatively linked to the amount of pesticide residues in soil. This indicates that pesticide residues, in addition to abiotic factors such as pH, are a key factor determining microbial soil life in agroecosystems. This comprehensive study demonstrates that pesticides are a hidden reality in agricultural soils, and our results suggest that they have harmful effects on beneficial soil life.
农药在全球农业生态系统中被大量使用。迄今为止，很少有研究评估有机管理农业土壤中农药的存在情况，也不清楚这些农药残留是否会影响土壤生物。我们采用包含 46 种农药（16 种除草剂、8 种除草剂转化产物、17 种杀菌剂、7 种杀虫剂）的分析方法，对 100 个有机和常规管理的农田进行了筛选。所有地点都发现了农药，包括 40 个有机农田。常规农田中农药残留的数量是有机农田的两倍，浓度是有机农田的九倍。与有机管理的持续时间相比，农药数量和浓度显著降低。即使经过 20 年的有机农业，仍有多达 16 种不同的农药残留。微生物生物量，特别是广泛存在的有益植物共生体丛枝菌根真菌的丰度，与土壤中农药残留的数量呈显著负相关。这表明，除了 pH 等非生物因素外，农药残留也是决定农业生态系统中微生物土壤生命的关键因素。这项全面的研究表明，农药是农业土壤中的一个隐藏现实，我们的结果表明它们对有益的土壤生物有有害影响。
