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

This Article Figures Only Full Text Free Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in ISI Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (6) Citing Articles via Google Scholar Google Scholar Articles by Ruan, H. Articles by Benjamin, J. G. Search for Related Content PubMed Articles by Ruan, H. Articles by Benjamin, J. G. GeoRef GeoRef Citation Agricola Articles by Ruan, H. Articles by Benjamin, J. G. Related Collections Structure and Properties Soil Models Other Soil Management

DIVISION S-6 - SOIL & WATER MANAGEMENT & CONSERVATION

Residue Cover and Surface-Sealing Effects on Infiltration

Numerical Simulations for Field Applications

^a USDA-ARS-NPA, Great Plains Systems Research Unit, P.O. Box E, 301 S. Howes St., Fort Collins, CO 80522
^b USDA-ARS-NPA, Central Great Plains Research Unit, Akron, CO 80720

Corresponding author (ruan{at}gpsr.colostate.edu)

Surface sealing of bare soils often reduces rain infiltration, and crop-residue cover is commonly used to reduce surface sealing. We conducted numerical experiments to quantify effects of the percentage and distribution of residue cover on infiltration, and to provide guidelines for residue management. Residue cover was simulated over the soil surface in circular patches. Excess surface water from the bare surface-sealed areas was available for infiltration in nonsealed areas. Numerical simulations were conducted for combinations of (i) soil type, either a clay loam or loamy sand soil; (ii) percentage residue cover (P_rc); (iii) saturated hydraulic conductivity of the surface seal (K_c) relative to bulk soil (K_s); (iv) residue-patch size with a constant P_rc; and (v) rainfall intensity. The K_c values had the greatest influence on infiltration as a function of P_rc. This influence increased with rainfall intensity. For a given P_rc, smaller patches gave greater relative infiltration due to differences in the lateral redistribution of infiltrated water. The target values of P_rc that provided 95% relative infiltration varied from 40 to 80% for most combinations. Changing the geometry of the residues made no significant difference. We also tested a one-dimensional model with a spatially averaged saturated hydraulic conductivity (K_ce) for both covered and surface-sealed areas, and found that infiltration into a partially residue-covered soil could be estimated by the one-dimensional model for all cases of this study, when K_c > 0. Finally, simulated infiltration qualitatively agreed with data sets of two independent field experiments under similar soil and rainfall conditions.

Abbreviations: P_rc, percentage residue cover • K_c, saturated hydraulic conductivity of the surface seal • K_s, saturated hydraulic conductivity of bulk soil • K_ce, spatially averaged saturated hydraulic conductivity • R₁, radius of the residue patch • R₂, radius of the cylinder

This article has been cited by other articles:

				L. R. Ahuja, L. Ma, and D. J. Timlin Trans-Disciplinary Soil Physics Research Critical to Synthesis and Modeling of Agricultural Systems Soil Sci. Soc. Am. J., February 2, 2006; 70(2): 311 - 326. [Abstract] [Full Text] [PDF]