Assessment of spatial variability of soil physical and hydraulic properties in Netravati catchment, Karnataka State, India

Abstract

Site specific management and precision agriculture seeks to identify and analyze variability in soil properties. Runoff prediction and sediment yield estimation using distributed hydrologic modeling requires spatially distributed soil data especially saturated hydraulic conductivity, water content and particle size distribution. Therefore, soil data becomes one of the major inputs in any watershed management studies. The present study was conducted to analyse spatial variability in soil physical and hydraulic properties in Netravati river basin, Karnataka State, India. The spatial interpolation of soil properties was carried out by using three methods such as Ordinary Kriging (OK), Inverse Distance Weighting (IDW) and Radial Basis Function (RBF). Results indicate that soil properties such as %sand, %silt and %clay are highly variable in nature with standard deviation value of 16.08, 13.27 and 8.82. The OK method is efficient in predicting sand, silt, clay and saturated hydraulic conducted. IDW and RBF methods predicted organic matter content and bulk density with acceptable error of 1.084%, 1.09% and 0.05gm/cc, 0.04gm/cc respectively.