This study presents a novel pesticide transport module for the OpenLISEM runoff and erosion model. During water erosion events, high amounts of pesticides can be transported alongside the runoff. Simulating this process helps to mitigate adverse effects of pesticides in the environment. We conceptualized pesticide uptake during runoff with a mixing-layer, including mass transfer of dissolved pesticides into the runoff water and detachment in combination with enrichment of sorbed pesticides. Lateral transport of pesticides is modelled with a kinematic wave based on the overland flow of water. The model simulations were in line with observations for two events in a small agricultural catchment in South-Limburg, the Netherlands. A sensitivity analysis showed that pesticide transport was mainly influenced by the mass transfer rate, the soil-water partitioning and the exponent for the enrichment ratio. The accurate simulation of runoff and erosion by OpenLISEM, enables OpenLISEM-pesticide to simulate transport and redistribution adequately.

本研究提出了一种用于 OpenLISEM 径流和侵蚀模型的新型农药传输模块。在水侵蚀事件期间，大量农药会沿着径流迁移。模拟这个过程有助于减轻农药对环境的不利影响。我们用混合层概念化了径流过程中农药的吸收，包括溶解农药向径流水中的传质以及分离与吸附农药的富集相结合。农药的横向输送通过基于地面水流的运动波进行建模。该模型模拟与荷兰南林堡省一个小型农业流域的两个事件的观测结果一致。敏感性分析表明，农药迁移主要受传质速率、土水分配和富集比指数的影响。OpenLISEM 对径流和侵蚀的精确模拟使 OpenLISEM-pesticide 能够充分模拟运输和再分配。