Impact of Land Use Changes on Soil Erodibility in the Outer Himalayas

Land use change hurts soil characteristics such as permeability, soil texture and aggregate stability, soil erodibility etc. which make soils susceptible to erosion and degradation.  The outer Himalayan region is prone to large-scale soil erosion by water owing to the vast disparity in the slope gradient, undulating relief, largely mountainous joined with high-intensity rainfall and lithological characteristics of these rocks. Soil erodibility, one of the key factors affecting the rate of erosion can be estimated by using various soil erodibility indices. In examining erodibility indices across various land use changes, it was evident that both the clay ratio (CR) and modified clay ratio (MCR) escalated as land use shifts from forest to more disturbed environments. As we transit from forest to agriculture, these ratios increased and were even more marked in the transition from forest to wasteland. The erosional behaviour as per CR and MCR in agriculture land use transitions could be arranged in the order that forest < agriculture