Fuzzy AHP Based Multi Crteria Decision Support for Watershed Prioritization

Abstract

The article presents an efficient multi-criteria decision support model (MCDSM) to prioritize susceptible areas in a watershed for soil conservation measures based on impact analysis of topography, climate, morphology, soil, land cover, management and conservation factors. The MCDS model has been developed based on fuzzy analytical hierarchical process (FAHP) by computing its weights of nine erosion hazard parameters (EHPs), which include; soil loss from revise universal soil loss equation model, sediment yield, sediment production rate, sediment transport index, slope, drainage density, channel frequency, form factor, and circulatory ratio. The MCDS model has successfully been applied to Benisagar reservoir catchment in Madhya Pradesh (India), comprised of 36 sub-watersheds for prioritizing areas require soil conservation measures. For computing weights of EHPs in FAHPs, triangular, narrow rectangular, medium rectangular and wide rectangular fuzzy membership functions have been used followed by the geometric mean method to determine the final weight matrix. The test of consistency ratio showed wide rectangular function as the most effective one in determining the weights of EHPs with soil loss as the most sensitive and circulatory ratio as the least sensitive parameter. The final priorities of the sub-watersheds have been determined using weight and their corresponding normalized values of EHPs. Based on the clustering of final priorities, the sub-watersheds have been categorized into four groups of priorities, i.e., very high, high, medium, low and very low for soil and water conservation measures. The derived methodology can successfully be used in prioritization of soil conservation measures in a basin for developing catchment area treatment plan.