Water Retention Characteristics of Various Soil Types under Diverse Rainfed Production Systems of India

The relationships of soil water retention at 1/3 and 15 bar and available water content with soil physicochemical properties were studied in 147 soil samples collected from 21 profiles from rainfed regions of the country. In general Vertisols and Vertic sub-groups showed higher water retention at 1/3 and 15 bars, and available water content. A number of profiles showed an increasing trend in water retention with increase in soil depth. Reduction in water retention from 1/3 bar to 15 bar was greater in Inceptisols/Entisols, Alfisols/Oxisols and Aridisols than in Vertisols. Amount of clay and CEC showed significant positive correlation, while sand showed negative correlation with soil water retention. The relationships between organic carbon and water retention in surface soils were non-significant. Multiple regression analysis for pooled soils (n=147) showed that EC, CaCO₃, sand, clay and CEC contributed to the variations in available water in soil.