Nutrient Cycling in Agroecosystems

, Volume 59, Issue 3, pp 269–284

Processes controlling soil phosphorus release to runoff and implications for agricultural management

  • R.W. McDowell
  • A.N. Sharpley
  • L.M. Condron
  • P.M. Haygarth
  • P.C. Brookes
Article

Abstract

Phosphorus (P) loss from agricultural land to surface waters is well known as an environmental issue because of the role of P in freshwater eutrophication. Much research has been conducted on the erosion and loss of P in sediments and surface runoff. Recently, P loss in sub-surface runoff via agricultural drainage has been identified as environmentally significant. High soil P levels are considered as a potential source of P loss. However, without favourable hydrological conditions P will not move. In this paper, we review the basis of soil P release into solution and transport in surface and sub-surface runoff. Our objectives are to outline the role of soil P and hydrology in P movement and management practices that can minimize P loss to surface waters. Remedial strategies to reduce the risk of P loss in the short-term are discussed, although it is acknowledged that long-term solutions must focus on achieving a balance between P inputs in fertilizers and feed and P outputs in production systems.

agricultural management agricultural runoff animal manures eutrophication phosphorus subsurface flow surface runoff 

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Copyright information

© Kluwer Academic Publishers 2001

Authors and Affiliations

  • R.W. McDowell
    • 1
    • 2
  • A.N. Sharpley
    • 3
  • L.M. Condron
    • 4
  • P.M. Haygarth
    • 5
  • P.C. Brookes
    • 6
  1. 1.Department of GeographyUniversity of CambridgeCambridgeUK
  2. 2.Pasture Systems and Watershed Management Research UnitUSDA-ARSUniversity ParkUSA
  3. 3.Pasture Systems and Watershed Management Research UnitUSDA-ARSUniversity ParkUSA
  4. 4.Soil, Plant & Ecological Sciences DivisionLincoln UniversityCanterburyNew Zealand
  5. 5.Institute of Grassland and Environmental Research, North WykeOkehampton, DevonUK
  6. 6.IACR-RothamstedHarpenden, HertsUK

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