Prioritization of watersheds using multi-criteria evaluation through fuzzy analytical hierarchy process

Abstract

Conservation of available natural resources through demarcation of potential zones at micro level are primary necessitate for sustainable development, particularly in the fragile semi-arid tropics.  Delineation of potential zones for implementation of conservation measures above the entire watershed at similar occurrence is inaccessible as well as uneconomical; consequently it is a prerequisite to apply viable technique for prioritization of sub-watersheds (SWDs).  Keeping this in view, the present research attempted to study various morphological characteristics and to implement Geographical Information System (GIS) and Multi Criteria Decision Making (MCDM) through Fuzzy Analytical Hierarchy Process (FAHP) techniques for identification of critical sub-watersheds situated in transaction zone between mountainous and water scarcity region of Western Part of India.  The morphometric characterization was obtained through the measurement of three distinct linear, areal and relief aspects over the eight sub-watersheds.  The morphometric characterization showed imperative role in distinguishing the topographical and hydrological behavior of the watershed.  Each hydrological unit was ranked with respect to the value and weightages obtained by deriving the relationships between the morphometric parameters obtained through classification of the SWDs by associating the robustness of fuzzy logic and the Analytical Hierarchy Processes (AHP).  Based on FAHP approach, sub-watersheds were evaluated as vulnerability assessment zones and alienated into five prioritization levels: very less, less, medium, high and very high classes.  The evaluated results illustrated that 60.85% of sub-watersheds (five sub-watersheds) were in the medium to high susceptible zones, which depicted potential areas for necessity of establishment of conservation interventions for the sustainable watershed management planning.  The FAHP based technique is a viable approach in illustrating the dilemma particularly over data hungry and complex conventional soil and water risk assessment methods and will be useful to various stakeholders (rural extension community, agriculturists and water resources managers) for better decision making with an obliging rule based system for implementing various assessment measures.

Keywords: fuzzy analytical hierarchy process, geographic information system, multiple criteria decision making, watershed prioritization