ESTIMATION OF WATER-RETENTION CHARACTERISTICS FROM THE BULK-DENSITY AND PARTICLE-SIZE DISTRIBUTION OF SWEDISH SOILS

Citation
K. Rajkai et al., ESTIMATION OF WATER-RETENTION CHARACTERISTICS FROM THE BULK-DENSITY AND PARTICLE-SIZE DISTRIBUTION OF SWEDISH SOILS, Soil science, 161(12), 1996, pp. 832-845
Citations number
47
Categorie Soggetti
Agriculture Soil Science
Journal title
ISSN journal
0038075X
Volume
161
Issue
12
Year of publication
1996
Pages
832 - 845
Database
ISI
SICI code
0038-075X(1996)161:12<832:EOWCFT>2.0.ZU;2-4
Abstract
A Swedish soils database containing soil-water retention data, particl e-size fractions, dry bulk. density, and organic matter content was an alyzed in order to find a relatively simple predictor of the soil-wate r retention curve (SWRC), As a SWRC model we chose a three-parameter f unction selected hom nine van Genuchten-type retention models that wer e fitted to the measured retention data by nonlinear parameter optimiz ation. Cumulative particle-size (CP) data were described by a logistic distribution model, Additionally, the mean and standard deviation of the CP distribution were estimated directly from the measured particle -size data, Regression equations were subsequently used to estimate th e parameters in the selected SWRC model from available soil properties , particle-size data, and CP distribution parameters, Four alternative pedotransfer models were formulated to estimate the SWRC curve from t he basic soil properties, These models predicted the SWRC curves from either the original soil data or from the CP distribution parameters, A mean estimation error of less than 2.5% was used to indicate a good estimation, The highest ratio (67%) of good estimations and the lowest ratio (12%) oh poor estimations were obtained when both the original soil properties and the CP model parameters were used, Our study shows that the resulting simple SWRC model gives a good description and a u sable prediction of the retention properties of Swedish soils for a wi de range of soil textures.