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 HighWire Citing Articles via Google Scholar Google Scholar Articles by Ahuja, L. R. Articles by Garrison, A. Search for Related Content PubMed Articles by Ahuja, L. R. Articles by Garrison, A. Agricola Articles by Ahuja, L. R. Articles by Garrison, A.

Changes in Soil Water Retention Curves Due to Tillage and Natural Reconsolidation

USDA-ARS, Great Plains Systems Research Unit, P.O. Box E, Fort Collins, CO 80522-0470

*Corresponding author(ahuja{at}gpsr.colostate.edu).

ABSTRACT

Changes in soil water retention of the surface soil brought about by tillage can significantly alter the amount of rain water that infiltrates into the root zone and is available for plant growth. Soil tillage generally increases porosity and changes the pore-size distribution, leading to changes in the soil water retention curve and hydraulic conductivities. The objective of this study was to investigate some simple ways of estimating the soil water retention curve of a tilled soil from that of an untilled soil, knowing the change in soil porosity or bulk density due to tillage. The study of literature and empirical analysis of the available data indicated: (i) under field conditions the tillage did not significantly change the air-entry value of the soil; (ii) tillage increased the absolute value of the slope of the log-log relationship below the air-entry value; and (iii) the changes due to tillage in the retention curve occurred only in the larger pore-size range, approximately between the air-entry pressure head value and 10 times the air-entry value. Assuming these observations hold in general, two simple methods of estimating the water retention curve of a tilled soil from that of its untilled condition are proposed. The first method is a simple imposition of the Brooks and Corey function between the air-entry value and 10 times this value. The second method assumes that the change in soil water content at a given pressure head in the above range of pressure heads was inversely proportional to the value of the pressure head. The tests on four pairs of measured water retention curves on three different soils showed that these methods provided good approximations.

Received for publication March 10, 1997.

This article has been cited by other articles:

				S. Assouline Modeling the Relationship between Soil Bulk Density and the Hydraulic Conductivity Function Vadose Zone J., May 26, 2006; 5(2): 697 - 705. [Abstract] [Full Text] [PDF]

				S. Assouline Modeling the Relationship between Soil Bulk Density and the Water Retention Curve Vadose Zone J., April 27, 2006; 5(2): 554 - 563. [Abstract] [Full Text] [PDF]

				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]

				D. A. Abrahamson, D. E. Radcliffe, J. L. Steiner, M. L. Cabrera, J. D. Hanson, K. W. Rojas, H. H. Schomberg, D. S. Fisher, L. Schwartz, and G. Hoogenboom Calibration of the Root Zone Water Quality Model for Simulating Tile Drainage and Leached Nitrate in the Georgia Piedmont Agron. J., November 17, 2005; 97(6): 1584 - 1602. [Abstract] [Full Text] [PDF]

				J. P. Fuentes, M. Flury, and D. F. Bezdicek Hydraulic Properties in a Silt Loam Soil under Natural Prairie, Conventional Till, and No-Till Soil Sci. Soc. Am. J., September 1, 2004; 68(5): 1679 - 1688. [Abstract] [Full Text] [PDF]

				T. Moroizumi and H. Horino Tillage Effects on Subsurface Drainage Soil Sci. Soc. Am. J., July 1, 2004; 68(4): 1138 - 1144. [Abstract] [Full Text] [PDF]

				F. J. Leij, T. A. Ghezzehei, and D. Or Analytical Models for Soil Pore-Size Distribution After Tillage Soil Sci. Soc. Am. J., July 1, 2002; 66(4): 1104 - 1114. [Abstract] [Full Text] [PDF]

				T. Katsvairo, W. J. Cox, and H. van Es Tillage and Rotation Effects on Soil Physical Characteristics Agron. J., March 1, 2002; 94(2): 299 - 304. [Abstract] [Full Text] [PDF]