non-point source pollutants

sediment

phosphorus

riparian land-uses

conservation land-uses

To improve stream water quality in the United States, government programs subsidize farmers to establish riparian conservation land-uses in agricultural landscapes. This study compared sediment and phosphorus water concentrations from stream reaches adjacent to riparian forest buffers, grass filters, row-cropped fields, pastures with cattle fenced out of the stream, and continuous, rotational and intensive rotational pastures in Iowa. In some cases agricultural land-uses had significantly higher sediment and phosphorus concentrations, while in others the conservation land-uses were higher. The few significant differences between conservation and agricultural land-uses suggest that the random placement of conservation land-uses is an inefficient way to improve water quality.