You could be reading the full-text of this article now if you...

If you have access to this article through your institution,
you can view this article in

Phosphorus Loss and Forms in Runoff From Watersheds in the Great Plains

Elrashidi, Moustafa A.1; West, Larry T.1; Persaud, Naraine2

Soil Science:
doi: 10.1097/SS.0b013e3182787406
Technical Article

Abstract: Increasing P loss from soils caused by runoff has contributed to contamination of surface waters in the Great Plains. Knowledge of P forms in runoff is necessary to develop appropriate land management practices and reduce the impact of P on water resources. A 2-year study was conducted on the Roca watershed, located in Lancaster County, Nebraska. This watershed is part of the Great Salt Creek watershed, which is considered a representative of watersheds in the Northern Great Plains. The objectives were to apply the Natural Resources Conservation Service technique to (i) estimate P loss from soils by runoff, (ii) determine P forms in the runoff, and (iii) estimate P loading and impact on water quality in Salt Creek. The annual loss of P by runoff was estimated at 17.7 tons for 2009 and 22.1 tons for 2010. These losses could be considered as the annual P loadings into Salt Creek. The predicted average dissolved P concentration in the runoff was 532 and 464 μg/L during 2009 and 2010, respectively. Most of the P measured in Salt Creek during the 2-year study was in the dissolved reactive (DRP) form (79%), and the remaining P was associated with suspended sediment, mainly in unreactive form (UP). The observed average DRP in stream water was 462 and 454 μg/L for 2009 and 2010, respectively. For each year, the predicted DRP was within 1 S.D. of the observed value. The data supported the applicability of the Natural Resources Conservation Service technique to estimate soil P losses and the impact on surface waters in the Great Plains.

Author Information

1U.S. Department of Agriculture/Natural Resources Conservation Service, Lincoln, NE. Dr. Moustafa A. Elrashidi is corresponding author.

2Virginia Polytechnic Institute & State University, Blacksburg, VA.

Address for correspondence: Dr. Moustafa A. Elrashidi, U.S. Department of Agriculture/Natural Resources Conservation Service, National Soil Survey Center, 100 Centennial Mall North, Lincoln, NE 68508; E-mail:

Financial Disclosures/Conflicts of Interest: None reported.

Received May 30, 2012.

Accepted for publication October 3, 2012.

© 2012 Lippincott Williams & Wilkins, Inc.