Abstract

The practice of large phosphorus (P) additions to agricultural land has resulted in an increased depletion of limited mineable rock phosphate resources, P accumulation in soils with an increased risk for P losses, and intensified eutrophication and deterioration of water quality in recipient water bodies. A number of measures have been used to reach balance between P inputs and outputs in agricultural systems, with the goal of achieving improved P use efficiency, sustained high crop yields and reduced P losses. This paper discusses how this goal may be achieved. Results from a Swedish long-term fertility experiment combined with results of a P leaching study using a selection of soils from the fertility experiment are used to evaluate the effects of a balanced P system on yields, soil P levels and P leaching. Three P fertilizer application strategies are compared (zero P, replacement P, and a treatment where surplus P fertilization was used to achieve a rapid increase in the soil P status). The replacement P strategy appeared to be the most sustainable system but P fixation in this system must be accounted for. When surplus P rates were applied, increased crop yields were counterbalanced by poorer use efficiency and P accumulation in soil. Topsoil P content was a poor predictor of P leaching. Instead, balancing P inputs and outputs represents a first step in the management of P losses, but additional, site-specific measures are required to counteract site-specific factors responsible for P losses

Published in

Soil Use and Management
2005, Volume: 21, pages: 94-101
Publisher: CABI PUBLISHING

SLU Authors

• Djodjic, Faruk

  • Department of Soil Sciences, Swedish University of Agricultural Sciences
    

• Bergström, Lars

  • Department of Soil Sciences, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Agricultural Science


Publication identifier

DOI: https://doi.org/10.1079/SUM2005305

Permanent link to this page (URI)

https://res.slu.se/id/publ/6522