Evaluation of soil salinity leaching requirement guidelines

Authors

John Letey, University of California, Riverside,Follow
Glenn J. Hoffman, University of Nebraska--LincolnFollow
Jan W. Hopmans, University of California, DavisFollow
Stephen R. Grattan, University of California, DavisFollow
Donald Louis Suarez, USDA Salinity Laboratory, Riverside, CAFollow
Dennis L. Corwin, USDA Salinity Laboratory, Riverside, CA,Follow
Jim D. Oster, University of California, RiversideFollow
Laosheng Wu, University of California, RiversideFollow
Christopher Amrhein, University of California, RiversideFollow

Date of this Version

2011

Citation

Agricultural Water Management 98 (2011) 502–506; doi:10.1016/j.agwat.2010.08.009

Comments

This article is a U.S. government work, and is not subject to copyright in the United States.

Abstract

Water for irrigation is a major limitation to agricultural production in many parts of the world. Use of waters with elevated levels of salinity is one likely option to meet the supply of increased demands. The sources of these waters include drainage water generated by irrigated agriculture, municipal wastewater, and poor quality groundwater. Soil salinity leaching requirements that were established several decades ago were based on steady-state conditions. Recently transient-state models have been developed that potentially can more correctly predict the dynamics of the chemical–physical–biological interactions in an agricultural system. The University of California Center for Water Resources appointed a workgroup to review the development of steady-state analyses and transient-state models, and to determine whether the current recommended guidelines for leaching requirement based on steady-state analyses need to be revised. The workgroup concludes that the present guidelines overestimate the leaching requirement and the negative consequences of irrigating with saline waters. This error is particularly large at low leaching fractions. This is a fortuitous finding because irrigating to achieve low leaching fractions provides a more efficient use of limited water supplies.