【摘要】 为研究苏北规模化灌区退水中极性农药对地表水体的污染特征、时空分布及生态风险，分别在农作物灌期，于2022年4月（枯水期）和9月（丰水期）对选择22条主要河流，在具有大量农田流域的支流设置25个监测点；采用全自动固相萃取结合高效液相色谱-串联质谱法对50个地表水样监测分析，结果表明，12种极性农药的检出限均低于0.1 ng/L，检出率最高的是阿特拉津，检出率为100%，最大检出质量浓度为4 402 ng/L；其他农药检出率由高到低的顺序分别为敌敌畏，克百威和乐果，检出质量浓度为ND～46 ng/L;S9是重污染区，采用风险熵指数对农药进行生态风险评估，丰水期地表水中的农药对水生生物的威胁大于枯水期，阿特拉津对水生生物的风险属于中风险，亟待关注。更多还原

【Abstract】 In order to study the pollution characteristics, spatiotemporal distribution and ecological risk of polar pesticides on surface water bodies in receding water of large-scale irrigation area in northern Jiangsu province, 22 major rivers were selected in April(dry season) and September(rainy season) in 2022, respectively. Fifty collected surface water samples were analyzed by solid phase extraction(SPE) combined with high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS). The results indicated that the detection limit of twelve polar pesticides was less than 0.1 ng/L, the detection rate of atrazine was 100%, the maximum detection concentration was 4 402 ng/L. The detection rates of other pesticides in order from high to low were dichlorvos, carbofuran and rogor. The detection concentrations were ND-46 ng/L. S9 is a heavily polluted area, and the risk quotient index was used to assess the ecological risk of pesticides. The threat of pesticides to aquatic organisms in surface water in rainy season was greater than that in dry rainy season, and the risk of atrazine to aquatic organisms was medium risk.更多还原