淡水水生生物对阿特拉津除草剂的敏感度

针对水环境中普遍存在的农药污染问题,以阿特拉津除草剂作为研究对象,梳理、整合阿特拉津对水生生态系统中不同营养级水生生物的急、慢性毒性数据,构建了基于对数-逻辑斯蒂分布的水生生物物种敏感度分布模型,分析并对比了阿特拉津对不同类群和不同区系水生生物急慢性毒性敏感度差异. 结果表明,水生动物和植物、无脊椎动物(包括甲壳类、昆虫类、软体动物和蠕虫类)和脊椎动物(包括鱼类和两栖类动物)对阿特拉津敏感度均存在显著差异. 分析了阿特拉津对不同类群水生生物的HC₅(5%危险浓度)值,其中对水生动物和植物的急性毒性HC₅值分别为4257.94和12.55μg/L,慢性毒性的HC₅值分别为2.47和1.95μg/L；对水生脊椎动物和无脊椎动物的HC₅值分别为7490.31和1611.76μg/L；对甲壳类和鱼类的HC₅值分别为1201.16和6639.90μg/L. 在保护95%的物种水平下,不同类群试验生物对阿特拉津的敏感度排序为水生植物>水生动物、水生无脊椎动物>水生脊椎动物、甲壳类动物>鱼类. 从统计学角度分析,中国水生动物与北美水生动物对阿特拉津的敏感度差异不显著. 但是,中美两国间相对特有水生动物物种对阿特拉津的敏感度存在一定的差异. 

Species Sensitive Distribution for Aquatic Biota Exposed to Atrazine in Freshwater

Pesticides have been paid attention during recent years because of their ubiquity and persistence in the environment and their important biological effects. In this study, the species sensitivity distribution model for atrazine, one widely used herbicide, was developed using a log-logistic distribution based on the acute and chronic toxicity data across various trophic levels. Furthermore, aquatic species sensitivities to atrazine were compared between different taxa and regions, and 5% hazardous concentration of the species (HC₅) of different taxa and regions were derived based on the species sensitivity distribution models. The results showed that there were significant differences between aquatic animals and aquatic plants, vertebrates (including fish and amphibians) and invertebrates (including crustaceans, insects, mollusks and worms). HC_5values for acute toxicity to aquatic animals and aquatic plants were 4257.94and 12.55μg/L; to vertebrates, invertebrates, fishes, crustaceans were 7490.31,1.76,9.90and 1201.16μg/L, respectively. HC_5for chronic toxicity to aquatic animals and aquatic plants were 2.47and 1.95μg/L, respectively. The sensitivity of different taxa to atrazine followed the order of aquatic plants > aquatic animals, invertebrates > vertebrates, crustaceans > fishes. Statistically, there was slightly difference between sensitivity distribution of the Chinese and American aquatic animals to atrazine. However, the species sensitivities to atrazine are different between China and America since these two countries have different representative species.