Abstract: Water is an important resource to the environment in the hyperarid zone.Owing to the influences of natural factors,the desertification process in Keriya river valley in historical period showed that the water system was decreased, and the natural oasis was changed into desert.The changes of modern environment is mainly caused by human economic activities.Two examples are given.One is the expanding of Yutian oasis due to the development of agricultural production ,and the another is the unreasonable interference by human-being, These lead to an unfavourable change to the environment, especially to the natural oasis in lower reaches of the river.The territorial management,taking the river valley as an unit,and rational utilization and development of water resources are the foundation of ensuring a stable ecology environment.Daheyan oasis is a natural landscape zone having special significance to exploring the environment change of arid zone and the plant succession.It is necessary and feasible to set up the natural protective zone,and to ensure 0.1-0.15 billion m3of water.The development of Yutian oasis and establishment of protective zone are supplemented each other.They are coexisted in same ecosystem of river valley, good results both in economy and ecology can only be achieved from careful land ecological programme, rational structure and overall arrangement of farming, forestry and animal husbandry, and reasonable management of land ecosystem in river valley.