A Distribution-determination Method of Conjunction Use District with Groundwater and Surface Water for Hetao Irrigation District Based on GIS

The implementation of conjunctive irrigation use of groundwater and surface water,as well as rational exploitation and utilization of groundwater,were effective and appropriate ways to save water and control soil salinization in Hetao irrigation district,Inner Mongolia.In this paper,the groundwater salinity data and soil lithology characters were analyzed by ArcGIS,and then the distribution map of groundwater mineralization were constructed applying spaced elamination method,and finally the distribution and conjunction use districts of groundwater and surface water were determined taking the situation of land use and the water quality requirement of agricultural irrigation into consideration.The results showed that dividing all salinity data into three spatial layer was feasible.And some spatial characteristics were present on the distribution map of groundwater mineralization.Conjunctive use districts of groundwater and surface water were mainly distributed in non-desert areas of Ulanbuh irrigated area,south of Jie Fangzha and Yong Ji irrigated area,north of Yi Chang irrigated area and its juncture areas with Urat irrigated area and Ulansu Hai,the tail end of Urat irrigated area,and there were also parts of the distribution area along the northern Lang Shan Mountains.The control area of conjunctive use districts of groundwater and surface water accounted for about 45% of the control area of all Hetao Irrigation District.