平原河网地区稻田农药脉冲输出迟滞分析研究  

Study on the hysteresis effect of pulse export of pesticides from paddy fields in the plain river network area

作　　者：陈诚 贾忠华[2] 罗纨[2] 刘文龙 CHEN Cheng;JIA Zhong-hua;LUO Wan;LIU Wen-long(State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants,Shanghai Academy of Environmental Sciences,Shanghai 200233,China;College of Hydraulic Science and Engineering,Yangzhou University,Yangzhou 225009,China)

机构地区：[1]上海市环境科学研究院,国家环境保护新型污染物环境健康影响评价重点实验室,上海200233 [2]扬州大学,水利科学与工程学院,江苏扬州225009

出　　处：《中国环境科学》2024年第6期3408-3418,共11页China Environmental Science

基　　金：国家自然科学基金资助项目(51979239)。

摘　　要：针对目前有关稻田施药后短期内农药的脉冲式输出过程及运移机理尚不十分明确的问题,以扬州市江都区农田水利科学研究站的试验稻田为研究区,针对稻田施药后农药面源污染物与排水的双脉冲输出过程开展高频监测,捕捉到毒死蜱、阿维菌素、三环唑和噻呋酰胺等4种水稻常用农药的脉冲式输出过程,结果显示:上述4种农药的输出浓度和负荷率峰值均发生在施药后2.5~5h内,输出脉冲特征明显.农药和排水双脉冲的相位关系受人为因素影响较大,呈现一定的随机性.对于淋溶性较好、受田间水文状况影响较大的农药(以杀菌剂三环唑和噻呋酰胺为代表),其迟滞指数分别为0.419和0.326,首次观察到较为明显的c-Q迟滞现象,该现象的发生与稻田施药先后顺序以及农药施入稻田后随水流运移到农沟水体的路径长短有关;而对挥发性较大的农药(以杀虫剂毒死蜱为代表),其迟滞系数仅为0.083,由于易受风向等不确定性因素影响未能观察到明显的迟滞现象.上述3种农药的FI值均等于或接近于1,说明排水脉冲对农药以富集作用为主.Currently there is a lacking of information on the export processes and the transport mechanism of pesticides shortly after application in paddy fields,so this paper presents an experimental study conducted in the Irrigation and Drainage Research Station of Jiangdu District of Yangzhou City in Jiangsu Province.The pulses of both field drainage and pesticides losses from paddy fields after application events were monitored with high frequency sampling.The pulse export processes of the pesticides which were normally used(chlorpyrifos,abamectin,tricyclazole and thifluzamide)were captured.The results indicated the peaks of concentration and load rate of the aforementioned pesticides occurred 5and 2.5h after application.The pulse export characteristics was obvious.The phase lag of pesticides and drainage was significantly influenced by anthropogenic factors and exhibited randomness to certain extent.For the more soluable fungicides(tricyclazole and thifluzamide),the hysteresis indices were 0.419 and 0.326,respectively.Their losses were much affected by the field hydrologic conditions,presenting an evident concentration and flow(c-Q)hysteresis phenomenon.Such phenomenon is related to the order of pesticide application in the paddy fields and the transport pathway of pesticides from fields to ditches.For the more volatile insecticide(chlorpyrifos),however,the losses were much affected by uncertain factors such as wind direction,no c-Q hysteresis phenomenon was observed with the hysteresis index of merely 0.083.The flushing indices of tricyclazole,thifluzamide and chlorpyrifos were equal to or close to 1,illustrating that the drainage pulse exhibited flushing effect to pesticides.Findings from this research may help understand the mechanism of pesticide pollutions in paddy environment and provide technical support for pesticide pollution control.

关 键 词：稻田 农药 面源污染 脉冲 相位关系 迟滞分析 

分 类 号：X592[环境科学与工程—环境工程]