APPRAISAL OF SOIL EROSION RISK IN THE EASTERN HIMALAYAN REGION OF INDIA FOR SOIL CONSERVATION PLANNING

Management practices to minimise soil erosion can be effectively carried out if the magnitude and the spatial distribution of soil erosion risk areas are known. Prioritisation of soil erosion risk areas is a challenging task, especially in the developing countries because of non-availability of relevant data and analytical tools for such an assessment. As a result, it becomes difficult to establish appropriate soil conservation measures on the risk-prone areas to reduce soil loss and ensure development of a sustainable management of soil resources. Such a database can be better generated and analysed in a geographical information system (GIS) environment to delineate and prioritise the soil erosion risk areas at state or regional level. Therefore, a methodology was developed to assess the soil erosion risks in eastern Himalayan region by integrating spatial data on prevailing erosion rates and soil loss tolerance limits in GIS environment. By comparing the potential erosion rates with permissible rates, we observed that about 5894 per cent of total geographical area (TGA) of the region requires different degrees of erosion management and 2838 per cent of TGA falls under no treatment category because of higher values of permissible erosion limits. It can be successfully applied to assess and prioritise soil erosion risks in any region or country and identify best management practices to bring the erosion losses within the permissible limits. Copyright (c) 2011 John Wiley & Sons, Ltd.