Spring water suitable and vulnerable watershed demarcation using AHP-TOPSIS and AHP-VIKOR models: study on Aizawl district of North-Eastern hilly state of Mizoram, India

摘要

Springs are one of the vital sources of water in the Mizoram district of North-Eastern hilly state of India. However, there is a paucity of literature on spring water serviceability, recharge potentiality and spring watershed management. Therefore, the present research aims to prepare spring water suitable and vulnerable watershed map of the Aizawl district using AHP-TOPSIS and AHP-VIKOR models. Highest relief, mean slope, mean annual rainfall, mean annual temperature, distribution of springs, geomorphic units, geological formations, stream order, concentration of lineaments and epicentre were considered as major spring suitability inducing factors. Besides, distribution of landslide, forest fire, forest cover area, built-up area, stone mining sites, proportion of agricultural land, degraded land, open area and water body were taken to measure vulnerability across watersheds. Relative analysis of AHP-TOPSIS (0-0.60) and AHP-VIKOR (0.04-1.00) shows that central part of the district is suitable for spring water. Study further reveals that hazard intensity and anthropogenic interventions are also very high in central part compared to other regions (AHP-TOPSIS-0.0-0.85 and AHP-VIKOR-0.0-1.00). Consequently, watershed suitable and vulnerable maps prepared in this study could act as a blueprint for spring management. Lastly, ROC curve shows that AHP-TOPSIS (0.816) is slightly better in its prediction compared to AHP-VIKOR (0.743).