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 Wu, L. Articles by Childs, S. W. Search for Related Content PubMed Articles by Wu, L. Articles by Childs, S. W. Agricola Articles by Wu, L. Articles by Childs, S. W.

Pore Size, Particle Size, Aggregate Size, and Water Retention

Dep. of Soil Science, 1991 Upper Buford Circle, Univ. of Minnesota, St. Paul, MN 55108

J. A. Vomocil

Dep. of Soil Science, Oregon State Univ., Corvallis, OR 97331

S. W. Childs

Cascade Earth Science, Ltd., P.O. Box 137, Corbett, OR 97019

*Corresponding author.

ABSTRACT

Measurements of water retention and pore-size distribution for a soil are time consuming and affected by changes in aggregate-size distribution. A method of compared distribution curves was used to relate distributions of pore size (PO), particle size (PA), aggregate size (AG), and pore size from water retention (WR). Seven surface soils varying in texture and aggregation were tested. After normalization to 100% volume, the pore-, particle-, and aggregate-size distribution, as well as water-retention (converted to pore diameter) curves were each fitted to a linearly transformed logistic function to evaluate their interrelations using R(m/n), a coefficient for the ratio of the diameters of component m to component n. Identical distribution curves have an R(m/n) value of 1. The R(PO/PA) and R(WR/PA) for the seven soils ranged from 0.25 to 2.26 and from 0.18 to 1.34, respectively, indicating that the theoretical packing parameters of 0.225 to 0.414 do not hold for PA distribution. The R(PO/AG) ranged from 0.06 to 0.23 and R(WR/AG) from 0.04 to 0.16. Both ranges of R values smaller than the theoretical packing parameters suggests interactions may occur between large and small aggregates. However, R(PO/AG) and R(WR/AG) values were more consistent and were significantly related to aggregation level and bulk density, suggesting that AG distribution should be used as a parameter to predict PO distribution and water retention. Comparisons between water retention curves and PO distributions from Hg intrusion gave R(PO/WR) ranging from 0.78 to 2.59, showing that equivalent PO for a given soil is not the same when different measuring methods are used.

Contribution of the Agric. Exp. Stn., Oregon State Univ. Technical Paper no. 9042.

Received for publication February 27, 1989.

This article has been cited by other articles:

				S. I. Hwang and S. E. Powers Using Particle-Size Distribution Models to Estimate Soil Hydraulic Properties Soil Sci. Soc. Am. J., July 1, 2003; 67(4): 1103 - 1112. [Abstract] [Full Text] [PDF]

				Y. Alami, W. Achouak, C. Marol, and T. Heulin Rhizosphere Soil Aggregation and Plant Growth Promotion of Sunflowers by an Exopolysaccharide-Producing Rhizobium sp. Strain Isolated from Sunflower Roots Appl. Envir. Microbiol., August 1, 2000; 66(8): 3393 - 3398. [Abstract] [Full Text]