Delineation of potential alternative agriculture region using RS and AHP-based GIS techniques in the drought prone upper Dwarakeswer river basin, West Bengal, India

Delineation of potential alternative agriculture region is an essential tactics of the drought prone to mitigate the harmful effect of drought for maintaining food security and sustainable economy. These alternatives can be integrated into existing cropping systems for providing additional income to farmers. The present study deals with site suitability analysis of alternative agriculture in the drought-prone upper Dwarakeswer river basin considering 15 parameters using Analytical Hierarchy Process (AHP) based Geographic Information System (GIS) techniques. The alternative agriculture zones are then delineated on the basis of 15 separate thematic layers such as Slope, landuse and landcover, soil depth, ground water, distance from roads, soil texture, distance from settlements, ruggedness index, drainage density, soil drainage, proximity to ponds, distance from vegetation, distance from streams, nitrogen and organic carbon. Finally, seven alternative agricultural zones are identified; these are plantation agriculture, integrated farming, fruit culture, folk rice culture, medicinal plant farming, mixed farming and horticulture covering an area of 96 km2, 234 km2, 295 km2, 341 km2, 298 km2, 199 km2 and 74 km2 respectively. This is also to note that the ‘Not Suitable Zone’ has been identified accounting 397 km2 area and covering 20.5% of total study area. A total of 350 alternative agricultural sites are identified for validation purpose and the computed kappa coefficient (k) of 95.34 denote a overall accuracy of 96%.