新烟碱类农药是世界农药市场份额最大的杀虫剂，被广泛应用于稻田的虫害防治。在目前推广的干湿交替灌溉模式下，稻田系统中该类农药的残留特征及迁移机制尚不清楚，这也是评价农药生态环境安全的前提。本项目拟以市场占比最大的三种新烟碱类农药（吡虫啉、噻虫嗪和噻虫胺）为研究对象，围绕影响其在干湿交替稻田中残留特征所涉及的主要迁移转化行为，开展三方面的工作：（1）通过单因子实验，探明各单一环境因子对水土系统中新烟碱类农药的吸附解吸及降解的影响。（2）在此基础上，进行稻田农药迁移转化模拟实验，探索干湿交替灌溉模式与其影响下的环境因子对新烟碱类农药在稻田中残留特征及多介质迁移的影响机制。（3）基于实验结果，构建实际稻田多介质迁移转化模型，捕捉临界干湿交替灌溉条件，提出可减少该类农药淋溶及残留的干湿交替调控途径。本项目可为新烟碱类农药在水环境系统中的归趋提供理论依据，也可为稻田水土安全与生态保护提供技术支撑。

Neonicotinoids, which grab the largest pesticide market share worldwide, are widely used in water environment system of paddy field. However, the information of migration and residual mechanisms of neonicotinoids in paddy field under alternate wetting and soil drying irrigation is still unknown. It is also the premise to evaluate the safety of pesticide ecological environment. The object of project is imidacloprid, thiamethoxam and clothianidin which are the largest neonicotinoids market share. This project attempts to discuss the key migration and transformation behaviors influencing multimedia residual of neonicotinoids, and carries out research work as follows three aspects: (1) Exploring the intrinsic relationship between single environmental physicochemical factor and the adsorption, desorption or degradation of neonicotinoids via single factor experiments. (2) Exploring the mechanisms of multimedia migration and residual influenced by alternating wet and dry irrigation via simulation experiment of pesticide migration in paddy field. (3) Constructing multimedia migration response model based on experimental results; capturing critical alternate wetting and soil drying irrigation conditions; providing technical approaches to improve the leakage and residual of neonicotinoids in paddy field. This project can provide theoretical basis for the neonicotinoids fate in aquatic environment system, and can provide technical support for water-soil security and ecological protection.