Identification of critical soil erosion prone areas and prioritization of micro-watersheds using geoinformatics techniques

Soil and water come under the category of the most important renewable natural resources on earth. But due to their indiscriminate use, they can be seriously endangered. Hence it is essential to manage natural resources sustainably to preserve them for the future. For soil prevention, Morphometric analyses only drainage pattern. However, Land Use/Land Cover (LULC) and soil characteristics should also be considered. Thus, it is necessary to combine all methods of prioritization to provide reliable results. As the Ganga watershed in India is currently under environmental distress, therefore in the present study, Morphometric, land use/land cover and Universal Soil Loss Equation (USLE) analysis are done in this watershed using ArcGIS and ArcSWAT. To identify the erosion prone areas for effective planning and management of groundwater resources the study area was divided into seventeen sub-watersheds for the analysis. The mainstream of the basin is of eighth order, and drainage patterns of sub-basins are mostly of sub dendritic to dendritic. Various linear, areal and relief parameters of each sub-watersheds have been determined, and sub-watersheds are prioritized by ranking them according to erodibility characteristic. The results reveal that according to Morphometric analysis out of seventeen sub-watersheds, Rajpura Region, Narahi Region and Mughal Sarai Region Sub-watersheds are subjected to more soil erosion, and Sarai Meer Region, Balia Region and Ghazipur Region Sub-watersheds are subjected to least soil erosion. Whereas according to LULC and USLE analysis Narahi Region, Pipra Region, Gahmar Region Sub-watersheds and Rajpura Region and Mughal Sarai Region Sub-watersheds are likely to be subjected to more soil erosion respectively. Sarai Meer Region, Lalganj Region, Pindra Region Sub-watersheds and Sarai Meer Region, Lalganj Region,Magharia Region Sub-watersheds are subjected to least soil erosion according to LULC and USLE analysis respectively. Integrating all the three methods, we found that Chandauli Region, Narahi Region and Mirzapur Region Sub-watersheds are suffering from severe soil erosion problem and Sarai Meer Region, Lalganj Region and Ghazipur Region Sub-watersheds have least soil erosion. These results can be further used for soil erosion and sediment yield modeling projects.