Assessing the influence of land use on groundwater pollution based on coefficient of variation weight method: a case study of Shuangliao City

In this study, the quality of groundwater was tested in 95 sampling wells in Shuangliao City. Based on the results, the coefficient of variation method was used to calculate the comprehensively evaluated value F, and the grade of groundwater quality, in accordance with the actual scenario in the study area, was classified according to the results of the evaluation. The spatial distribution of groundwater quality types in the study area was classified. In addition, the influence of human activity on each groundwater subsystem was assessed. Combined with the land use types in the study area, the Circle model was used to extract the land use types in the circular buffer zone with a radius of 500 m, and the Kendall rank correlation test was used to analyze the influence of the land use types on the spatial distribution of groundwater pollution. Based on the coefficient of variation, the groundwater quality standard was divided into four sections considering the actual scenario: <= 0.92 (I), 0.92 similar to <= 1.75 (II), 1.75 similar to <= 2.40 (III), and > 2.40 (IV). Water from class II was considered the main type for groundwater quality. NO3-, TFe, and Mn were deemed the main indexes of groundwater pollution. Further, land use type was found to have a great influence on the spatial distribution of groundwater pollution; specifically, dry land, paddy field, areas with dense traffic, and residential areas are the main land types that affect the groundwater environment.