HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Montgomery, J. A. Articles by McCool, D. K. Search for Related Content PubMed Articles by Montgomery, J. A. Articles by McCool, D. K. Agricola Articles by Montgomery, J. A. Articles by McCool, D. K.

Evaluating Soil Movement Using Cesium-137 and the Revised Universal Soil Loss Equation

Environmental Science Program, 1036 W. Belden Ave., DePaul Univ., Chicago, IL 60614

A. J. Busacca and B. E. Frazier

Dep. of Crop and Soil Sciences, Washington State Univ., Pullman, WA 99164

D. K. McCool

USDA-ARS, Land Management and Conservation Research, Pullman, WA 99164

*Corresponding author (jmontgom{at}wppost.depaul.edu).

ABSTRACT

More complete information is needed on the rates and patterns of soil movement in Palouse watersheds to better guide conservation planning. Water erosion has historically been predicted from rates using the Universal Soil Loss Equation (USLE) or the Revised USLE (RUSLE). These equations, however, do not account for deposition or tillage erosion. This study was conducted to assess patterns of soil movement in an open Palouse watershed during a 27-yr period using the ¹³⁷Cs tracer technique and to statistically compare transect- and point-based RUSLE soil loss rates with ¹³⁷Cs-based soil loss rates measured at 74 ¹³⁷Cs sampling points located on 89 landscape profiles. One hundred fifty-eight soil samples were collected from a modified grid pattern and analyzed for ¹³⁷Cs activity. Soil movement rates were interpolated at 8025 points in the sample grid using ordinary point kriging. Hillslopes were classified into geometric and geomorphic components. The kriged mean net soil movement rate for the 27-yr period was –3.3 kg m^–2 yr^–1. Doubly convex landscape positions have experienced the most severe erosion, apparently due to tillage erosion. The measured ¹³⁷Cs and transect-based RUSLE median soil loss rates were both significantly higher than the point-based RUSLE median; however, no significant difference existed between the transect-based RUSLE and measured ¹³⁷Cs median soil loss rates ( = 0.05). Meaningful comparisons between ¹³⁷Cs and RUSLE soil loss rates can only be made if a tillage movement rate, history of crop management, and the accuracy of RUSLE relationships and operating files are known.

Contribution from the Agric. Res. Center, College of Agric. and Home Economics, Washington State Univ. This work forms scientific paper no. 9508-24 of the Dep. of Crop and Soil Sciences, Washington State Univ. This study was undertaken with funding from the Washington Conservation Commission under their Centennial Clean Water Fund Grants Program and from the USDA Solutions to Environmental and Economic Problems (STEEP) Program.

Received for publication January 16, 1996.