Herbicide distribution and transport in subsurface environment of a tomato field in the Three Gorges Reservoir area, China

Abstract

The presence of pesticides via non-point source (NPS) pollution might be a threat to human health and aquatic ecosystems. This study aims to characterize quantitatively the distribution and transport of Linuron in a coupled canopy-soil system by using modelling techniques, viz. an integrated pesticide transport modelling system to simulate three-phase pesticide fate and transport in a tomato field of the Three Gorges Reservoir area. Results indicate that spatio-temporal distributions of Linuron levels in surface soil are dominated by its properties, rainfall, irrigation and its applications. The occurrence and distribution of Linuron in subsurface and deep soil are closely related to the cumulative and delayed effects. Runoff and erosion also play important roles in the environmental transport and fate of Linuron. The results may be useful for taking effective pesticide management measures to control pesticide NPS pollution at watershed scales.