气候变化领域集成服务门户

Targeting cropland retirement programs to reduce agricultural nonpoint source pollution is accomplished by employing disaggregated information about physical and economic factors that influence the benefits and costs of adopting specific erosion control practices on specific land parcels. The agricultural nonpoint source (AGNPS) model is used in a Minnesota watershed to simulate the relative effectiveness of alternative targeting schemes with respect to budget outlays for annual payments to landowners, reduction in downstream sediment yield and nutrient loss, and reduction in on-site erosion. Cost-effectiveness increased with information on economic factors (the opportunity cost of retiring a parcel of land) as well as on physical factors (contribution of a parcel to downstream sediment yield). The marginal cost-effectiveness of all schemes decreased as the enrolled proportion of watershed land increased.