Indian Journal of Soil Conservation

Land use decisions should be based on comprehensive and quantified assessments of the biophysical, environmental and socio-economic factors. Sustainable land use should have maximum suitability and minimum vulnerability. Hence, from the perspective of sustainability, an environmental suitability index (ESI) was developed in this study under hill and mountainous watershed to serve as most environmental friendly answer for the two key questions in land use planning; viz., what areas can be opened up for agricultural land and what landuse and management practices can be adopted. Land Suitability Index (LSI) for cropping was derived based on soil site rating. Erosion Tolerance Index (ETI) was established from the integration of soil loss tolerance (T-value) and average annual soil loss (A) and Environmental Suitability Index (ESI) was then generated from a convex combination of LSI and ETI. Land suitability index (LSI) provided the answer for the former question without considering the risks associated with it. Hence, a comparative analysis of the different methods such as Environment Suitability Index (ESI), site suitability methods of FAO and its modified form proposed by NBSS&LUP, Nagpur have been tried to address the issue of maximum suitability and minimum vulnerability. The study indicated that the normal site suitability criteria always provided under-estimation for marginal suitable category (ESI<0.3). For moderately suitable category (ESI=0.4–0.6) the land area in the watershed matched with normal site suitability for upland paddy (131 ha) and wheat (131 ha). In case of moderately suitable category about 135 ha was qualified as per ESI estimation. Qualitative approach (as per the FAO and it's modified form) resulted an over-estimation for soybean and pulses and under-estimation for maize and minor millets. The three categories of the land in the watershed were further analyzed for identifying soil constraints and suggesting suitable soil management strategies for each landuse type to minimize the risks factors. The strategies include the synchronizations of time of sowing of pulse crops with the onset of monsoon; diversified land use through agri-horti, silvipastoral systems and restocking through planting and protecting the forest areas in the watershed. This approach will provide information concerning landuse options whereby the landuse distribution can be optimized for improving ecological soil functions.