The Management of Soil Phosphorus Availability and its Impact on Surface Water Quality
A. N. Sharpley, Ardell D. Halvorson
Abstract
An increased public perception of the role of agriculture in nonpoint source pollution, has prompted an urgency in obtaining information on the impact of current and proposed agricultural management practices on surface water quality. This chapter discusses the role of agricultural management in maximizing soil phosphorus (P) availability, while minimizing P losses in runoff. It explains the effect of soil management on the dynamics of organic and residual P availability. Manure and organic wastes can be a valuable source of P to crops, improve soil physical properties, and increase soil organic matter content. As for fertilizer and animal manure management, the composition, rate, placement, and time of application are major factors affecting soil P availability. Accurate predictions of soil P availability and its transport in runoff are required to evaluate the relative effects of current and proposed agricultural management practices on the biological response of a water body.