关键词: 主离子特征, 水质评价, 浅层地下水, 模糊综合评价, 河西走廊

Abstract: In order to find out the main ion characteristics and water quality of shallow groundwater in the Hexi Corridor in Gansu Province, the hydro-chemical indexes of 75 water samples in the study area were analyzed comprehensively by mathematical statistics, Piper diagram, correlation analysis, Gibbs diagram and ion proportional coefficient method. Fuzzy comprehensive evaluation and Nemerow index method were used to evaluate the water quality of shallow groundwater. The results show that the shallow groundwater in the Hexi Corridor are generally alkaline. Cl-, Na+, K+, NO-3,and SO2-4 show variability in space. In general, the hydro-chemical type is bicarbonate sulfuric acid water. Na+, SO2-4, and Cl- in the shallow groundwater may come from the same source. Hydro-chemical compositions are mainly controlled by evaporation-precipitation, dissolution of silicate minerals, evaporated rock salts and sulfates. The result of water quality evaluation shows that the shallow groundwater quality of human aggregation is poor.

Key words: main ion characteristics, water quality evaluation, shallow groundwater, fuzzy comprehensive evaluation, Hexi Corridor