Prospects for Controlling Nonpoint Phosphorus Loss to Water: A UK Perspective

Accelerated losses of P from intensively managed farmland can contribute to eutrophication problems in fresh waters, and improved nutrient and land management practices may be required in sensitive watersheds to help maintain good water quality for a range of users. Control of background P losses caused by increases in soil P status require long‐term strategies to reduce surplus P inputs, since excessive soil P accumulation cannot be rectified quickly. However, targeted actions aimed at controlling the transport of soil P, and/or preventing the often significant losses of P that occur following the application of fertilizers and manures to the land surface, are needed to achieve the more short‐term reductions in P export required to overcome the effects of eutrophication. The challenge is to identify which mitigation options can be implemented most cost‐effectively under the operating site hydrological conditions. Prospects for control of nonpoint P loss are discussed in relation to recent initiatives introduced in the UK where, in the absence of specific regulatory drivers for control, reductions in P loss must rely on voluntary actions taken collectively within the watershed. Integrated control strategies could be implemented, often at relatively low cost and/or with financial advantage to the farmer. Practical management tools are required to help stakeholders identify the key problem areas and avoid them through more precise nutrient and land management. Nutrient management remains a key issue since controls over manure P inputs, and the way they are handled, will have the greatest socioeconomic impact at a range of scales.