Models for the Analysis of Agricultural Nonpoint Source Pollution

Mathematical models are useful means of analyzing agricultural nonpoint source pollution. This review summarizes and classifies many of the available chemical transport and planning and management models. Chemical transport models provide estimates of chemical losses from croplands to water bodies and include continuous simulation, discrete simulation and functional models. A limited number of transport models have been validated in field studies, but none has been tested extensively. Planning and management models, including regional impact, watershed planning and farm management models, are used to evaluate trade-offs between environmental and agricultural production objectives. Although these models are in principle the most useful to policy-making, their economic components are much better developed than components for prediction of water pollution