An improved FAHP based methodology for groundwater potential zones in Longchuan River basin, Yunnan Province, China

Abstract

Longchuan River Basin is located in Chuxiong (central Yunnan province, China) that is subject to severe drought. Agriculture is critical to local economy, which can lead to intense agricultural activity. Accordingly, delineating groundwater potential zones and developing usable groundwater resources are required to meet potable and irrigating water demands in the zone. Remote sensing (RS), geographic information system (GIS) and improved fuzzy analytic hierarchy process (FAHP) were adopted to delineate the groundwater potential zones to assess the groundwater availability in Longchuan River Basin. The surveys of China geological map, Landsat 8 OLI and GDEM Aster satellite images were employed to generate eight thematic layers, i.e., lithology, land use/land cover (LULC), lineaments density, rainfall, slope, normalized difference vegetation index (NDVI), drainage density and elevation; subsequently, the mentioned layers were converted into raster data in ArcGIS. According to the ability of thematic layer to impact groundwater potential, the mentioned criteria were weighted differently by improved FAHP. Next, a map based on weighted linear combination (WLC) model was generated. Lastly, the groundwater potential zones of study area fell into ‘poor’ zone, ‘moderate’ zone and ‘good’ zone. As revealed from the results of the study, nearly 31.22% of the area exhibited ‘good’ groundwater potential, approximately 36.46% was terrain exhibiting ‘moderate’ groundwater potential, and the residual 32.23% were considered to exhibit ‘poor’ groundwater potential. The results provide more insights, and the groundwater potential zones map can be exploited by local governments for groundwater resources management and exploitation.