Prioritization of sub-catchments of a river basin using DEM and Fuzzy VIKOR

Abstract

Fuzzy VIKOR, a decision making technique, is applied to prioritize 224 sub-catchments of Mahanadi Basin, India. Seven geomorphology based criteria viz., drainage density, bifurcation ratio, stream frequency, texture ratio, form factor, elongation ratio and circulatory ratio are estimated from five digital elevation models (DEMs). Triangular membership functions were formulated for each criterion for each sub-catchment which are based on individual values obtained from individual DEM’s. Entropy method is employed for estimation of weights of criteria and a similar mechanism is followed while formulating triangular membership function for weights. Eight groups are formulated with a number of sub-catchments in each group as 5, 26, 69, 65, 29, 11, 12, 7 for taking up conservation measures. Effect of varying strategy weight, (ν) on the ranking pattern is also studied and found that ν value effects ranking pattern significantly.