Vulnerability Assessment And Functional Zoning Of Groundwater In Kuitun River Basin Plain

The Kuitun River Basin is located in the western part of the North Tianshan Mountains and the southwestern part of Junggar Basin.Groundwater is the main source of water supply for production and residential in Kuitun River Basin.However,because of the human activity impact on the environment,poses potential crisis on groundwater system.In order to rationally utilization groundwater resources and prevent groundwater pollution,the groundwater vulnerability assessment and functional zoning in Kuitun River Basin plain area were carried out.The improved DRASTIC model and the combined weighting method of AHP and CRITIC were used in this paper to establishes an evaluation model assess groundwater vulnerability in the plain area of Kuitun River Basin;AHP method and expert scoring method were used to construct the groundwater functional zoning index system and carried out groundwater functional zoning.Finally,combined with the vulnerability assessment and functional zoning,the protection targets of groundwater quality and the control indexes of water quantity and water level in the study area were proposed.The main conclusions are as follows:(1)The DI scores of the anti-fouling performance of the aquifer ranged from 2.82 to 6.33 in the plain area of Kuitun River Basin.The areas with high vulnerability are mainly distributed in Ganjiahu forest farm,which accounts for 18.53%of the plain area.The area with poor vulnerability and that the groundwater is not easily be polluted.The areas with poor vulnerability are mainly distributed in the southeast of the Kuitun River Basin Plain,which accounts for 18.28%of the plain area.The areas with poor vulnerability and vulnerable to groundwater pollution are the target areas for water quality protection.Poor vulnerability and higher vulnerability area are mainly distributed in the middle of the plain area,with an area of10362.74 km~2,which accounts for 63.19%of the plain area.(2)The evaluation results showed that in the resource function evaluation,the weak resource function area covers 7822.98 km~2,which account for 47.70%of the plain area,mainly distributed in the gravel plain and the western part of the basin.The high resource function area covers 167.75 km~2,which account for1.02%of the plain area,which is mainly distributed in 84hu town and Jiahezi town.In the ecological function assessment,the weak ecological function area covers 9984.16 km~2,which account for 60.88%of the plain area,mainly distributed in the eastern part of the study area;The area with high ecological function covers 479.18 km~2,which accounts for 2.92%of the plain area,which is mainly distributed in 125regiment and the lower part of Jorton Allison Desert.(3)Based on groundwater function zoning the groundwater in the study area were divided into 3first-level zones and 8 second-level zones.The groundwater utilization area accounts for 38.06%of the plain area,among which the large-scale decentralized development and utilization area is the most widely distributed in the area,which accounts for 36.91%of the plain area;Ecological reserves are divided into four types of secondary areas,in which natural vegetation reserves accounts for is 18.97%of the plain area.Resource and ecological fragility can be divided into two types of secondary zones,and restricted mining areas accounts for 2.92%of the plain area.(4)Based on the vulnerability evaluation results,the study area was divided into non-protection area,general pollution protection area,pollution sensitive area and pollution severely sensitive area,the protection target were set up for the water quality protection and put forward the water quality protection measures.(5)The water quantity control indexes for the centralized scale mining,the scale decentralized development and utilization area are 21.48 million m~3and 78.91 million m~3in 2025,respectively.The water quantity control indexes are 20.79 million m~3and 70.32 million m~3in 2030,respectively.In 2025 and2030,the control rate of water level in the over-exploitation area are 0.10 m/a and 0.20 m/a,respectively.