Research On Karst Groundwater Vulnerability Evaluation Of Niangziguan SpringArea

Carrying out the vulnerability assessment of karst groundwater in Niangziguan spring area can provide technical support for the rational development and utilization of karst groundwater in the spring area and scientific and effective protection.It has important practical significance for economic and social construction and ecological environment protection in the spring area.The evaluation method of the vulnerability of karst groundwater in Niangziguan spring area used the superposition index method.The indexes of water quality vulnerability assessment are Depth of water table,Recharge of infiltration,Soil media,Topography,Land use type,Overlying layer and Abundance of aquifer.The index of water quantity vulnerability assessment is Recharge of infiltration,Coefficient of groundwater exploitation,Thickness of aquifer,and Abundance of aquifer.The weights of water quality and water vulnerability assessment indicators were determined by analytic hierarchy process.From this,it was determined that the water quality vulnerability assessment was the DRST_gLOA model,and the water quantity vulnerability assessment was the RCT_kA model.Based on this the zonation of karst groundwater vulnerability in Niangziguan spring area was obtained,and corresponding protection measures were obtained.Research results:The area with high water quality vulnerability is about 106km~2,accounting for 1.47%of the total area.It is distributed in the outcrops of the springs,Jucheng Town,Wenhe leakage area,Taohe leakage area,Songxi River leakage area,and Yuweng Reservoir.The leakage area and the leakage area of Dashimen Reservoir should be focused on water quality supervision and protection in this area.The area with high water quality and vulnerability is about 1138km~2,accounting for 15.77%of the total area.It is distributed in the bare carbonate area and its surroundings in the spring.The area with medium water quality is about 1530km~2,accounting for 21.20%of the total area.It is distributed in parts of Pingding County,central part of Yangquan City,east part of Xiyang County,east part of Heshun County,east part of Zuoquan County,part of Yu County,The central part of Shouyang County and most of Taiyuan City.The area with low water quality is about 3452km~2,accounting for 47.83%of the total area,distributed in the west of Pingding County,the west of Yangquan City,the west of Xiyang County,the west of Heshun County,the west of Zuoquan County,Yu County Southwest of China,most of Shouyang County,most of Yuci City,and east of Taiyuan City.The area with low water quality is about 991km~2,accounting for 13.73%of the total area,distributed in the southwest of Pingding County,part of the urban area of Yangquan City,the west of Xiyang County,the west of Heshun County,the northwest of Zuoquan County,Yu County The western part of China,Shouyang County and Yuci City.The area with high water vulnerability is about 160km~2,accounting for2.21%of the total area.It is distributed in the southwest and east of Pingding County,north of Niangziguan Quankou,and south of Shouyang County.In this area,water monitoring and protection should be focused.The vulnerable area with high water volume is about 1850km~2,accounting for 27.63%of the total area.It is distributed in most of Pingding County,the west and north of the urban area of Yangquan City,the southeast and northwest of Shouyang County,and the north of Yuci District.The whole territory of Taiyuan City.The area with medium water fragility is about 3431km~2,accounting for 47.55%of the total area.It is distributed in Pingding County,southeast of Yangquan City,most of Yu County,midwest of Shouyang County,and south of Yuci City.The area with low water vulnerability is about 1755km~2,accounting for 24.31%of the total area,distributed in the southeast of the urban area of Yangquan City,the south and east of Yu County,the east of Xiyang County,the east of Heshun County,and the east of Zuoquan County.The area with low water vulnerability is about21km2,accounting for 0.30%of the total area,and is distributed in the Youweng Reservoir leakage area,Yijing Town,east of Xiyang County,east of Heshun County,east of Zuoquan County side.