Analysis of Groundwater Quality Change Trend and Pollution Factors in Shanxi Province from 2016 to 2020

From 2016 to 2020, the water quality of 1139 groundwater monitoring points in Shanxi Province was investigated and studied to examine the water quality exceeding standard factors and times, water quality category evaluation results, etc. Based on the national standard, the groundwater quality of Shanxi Province was analyzed and evaluated by using the single component evaluation method and the comprehensive evaluation method of groundwater quality. The research results showed that the proportion of Ⅰ-Ⅲ water in each monitoring point was less than 75%, and the proportion of V water was less than 20%. The overall groundwater quality in Shanxi Province was in a state of mild pollution; the groundwater pollution in Shanxi Province mainly occurs in shallow pore water. The karst water and fissure water in the middle and deep layers are less affected. Fluoride has a greater impact on the groundwater quality in Shanxi Province, and the impact of ammonia nitrogen on groundwater quality gradually decreased with time. It showed a decreasing trend from south to north, and chloride ion was the main factor causing pore water pollution. Total hardness, total dissolved solids and sulfate ions have a greater impact on karst water pollution.