Priority Assessment of Sub-watershed Based on Optimum Number of Parameters Using Fuzzy-AHP Decision Support System in the Environment of RS and GIS

Abstract

Identification for planning of land and water resource management based on efficient decision-making tool is very important for providing appropriate weightage in stressed site. In the present study, fuzzy analytical hierarchy process (FAHP) with different erosion hazards parameters (EHPs) have been used as a pronouncement for identification of naturally stressed sub-watershed in Nagwan watershed of Hazaribagh district in Jharkhand, India. In fuzzy-AHP, analytical hierarchy process (AHP) builds a hierarchy (ranking) of decision items using comparisons between each pair of items expressed as a matrix with fuzziness. Paired comparisons produce weighting scores that measure how much importance items and criteria have with each other and checking the consistency of the decision. In this study, the Nagwan watershed was divided in 21 sub-watershed which varies from 2.34 to 7 km2 and all EHPs of sub-watersheds have been computed using remote sensing and GIS. From the study, it has been observed that best consistency ratio has been found when using 13 parameters that is 9.44 with narrow trapezoidal shape. Each morphometric parameter was ranked with respect to the value and weightage obtained by deriving the relationships between the morphometric parameters obtained through classification of the SW by associating the strength of fuzzy analytical hierarchy processes (FAHP). By this weight, the results revealed that the priorities in five categories, out of 21 sub-watershed 19 and 24% sub-watersheds qualify for very high and high priority, whereas 57% sub-watersheds fall under medium, low and very low priority.