ABSTRACT
ABSTRACT: Heihe River Basin is the second largest inland river basin in the arid northwest China. In arid inland basin, the core problem is water resources, while the core area is an oasis. It is a complex interdependence of Irrigation District, through spatial integration after the formation of the modern oasis. Under the strong control and guidance of the artificial canal system, water supply quantity determines Irrigation District, and irrigated land determines population carrying capacity, so water-soil-human systems exist a high degree of interdependence and symbiosis. All of irrigation units in Zhangye, the average of coupling degree about settlements and water, soil resource is 0.714 and the spatial differences are significant. The spatial distribution characteristics of the coordination degree is essentially similar coupling degree. Accordingly, the 27 irrigation districts can be divided into the water-soil-human resources harmonious area; water-soil-human resources run-in areas; water-soil-human resources antagonistic area; water-soil-human resources low coupling region.
