Abstract

The need to evaluate the potential risks of pesticides usage that may lead to contamination of water resources has been the reason behind the development of models for predicting pesticide leaching in soils and watershed areas. Various assessment models have been developed in the past. For example, the vulnerability of groundwater to pesticide leaching may be evaluated by indices and overlay-based methods, by statistical analyses of monitoring data, or by using process-based models of pesticide fate. Most of these models have been applied in various parts of the world but with little or none applicability in Nigeria. Since Nigeria is an agrarian country whose soils and water resources have suffered severely from the effects of pesticide contamination, the need to inform decision on applicability of some of these models becomes paramount. This paper thus provide a descriptive synthesis of some of the models used in predicting pesticide leaching in underground water and make recommendation for their usage in assessing groundwater contamination effects resulting from agricultural processes in Nigeria.

Key words: Groundwater, model, pesticide, hydrologic, simulation, management.