Morphometry based Sub-watershed Prioritization Using MCDMs in Non-Fuzzy and Fuzzy Dividends

Prioritization of sub-drainage systems is quintessential in regard to preparing a layout prior to the implementation of any soil and water conservation program. Most of the sub-watershed prioritization approaches find their linkages with the morphometric indices, nevertheless, a frugal and nimble approach for this prioritization exercise using the morphometry is still impending. The conferred study is an attempt towards filling this gap via the use of a statistical cum Mutli-Criteria Decision Making approach for the upper reaches of the Saryu watershed in the Bageshwar district of Uttarakhand Western Himalaya. The study area is a sixth-order drainage system with a geographical extent of 779.05 sq. km and is subdivided into 14 sub-watersheds using SWAT 2012. For the developed watersheds, 14 morphometric parameters, which primarily affect runoff and sediment response are computed and are dispensed as CRITIC inputs towards setting up relative priorities within them. The results from CRITIC were then used to assign ratings for AHP and FAHP, with the latter technique being solved via two methods, namely, geometric mean and extent analysis. A comparison of results suggested that AHP and the geometric mean method for FAHP engendered identical prioritization, while, the extent analysis nullified the effect of seven of the relatively low-rated morphometric parameters, thus producing different results. The study also advocated the use of the deliberated method in the context of managing a larger number of input morphometric parameters, along with their selection for auxiliary prioritization.