Unfolding the feasibility of rabi cropping through soil moisture characterization in Sibsagar district of Assam, India

Characterization of soil water retention properties coupled with feasibility of growing rabi crops during post kharif period were carried out in this study. Soil samples from profiles located at different physiography were collected. It was observed that water retention is high at the FC and minimum at PWP. Water retention study showed that the release behavior differed according to the soil texture. Bulk density was seen to be negatively correlated with 0.33 bar (−0.597**) and 15 bar (−0.637**). Clay hold significant and negative correlation with all the sand fractions and high positive and significant correlations with 0.33 bar (0.730**) and 15 bar (0.744**). Regression study showed that at 0.33 bar a maximum of 75.68% variability could be explained by bulk density, organic carbon parameters, silt, clay with some sand fractions whereas at 15 bar, bulk density, organic carbon and to a great extent clay played a key role to account for 74.5% variability. The total available water (TAW) and readily available water (RAW) for rabi crops like lentil, moong, bengal gram, sesame differed. The study indicated that light soils could supply water for a period of 10 to 13 days, medium soils for 29 to 33 days and heavy soils for 28 to 37 days. It was found that the light soils would suffer from severe water stress in the initial stage and the other soils at latter part of the growing periods causing failure of crops. Therefore, rabi cropping based on only AWC of soils would not be feasible during post-kharif period in the district.