关键词: 黑河流域, 绿洲, 土地资源, 优化配置

Abstract: In this paper,systematic methods of modern physical geography are employ ed for studying some issues of land resources optimum disposition in the Heihe River Basin in accordance with a lot of materials of the field survey and the base of former study.The land resources involve following characteristics,i.e.,there are rich land resources and various land types,oasis areas are surrounded by vast deserts,the qualitative differences among different kinds of lands are great,there are vast areas of land hard to use and of low-and medium-yield farmlands,the spatial combination of water and land resources is malposition,and eco-environment is fragile.The general principles of land use are put forward,that is,adjusting agricultural structure and extending the proportion of animal husbandry;energetically and rationally arranging crops in light of local advantages of light,heat,water and soil;overall planning the whole basin and giving full play to land potentialities;coordinating the benefits of economy,ecology and society,and protecting the environment.The lands in the drainage area are divided into follow ing four regions according to the combination feature of agricultural resources:(1) In the Qilian Mountains,which is the upper reaches of the Heihe River,it is highly important to protect forest and conserve water through afforestation,and rationally exploit grasslands.Extensive animal husbandry in the mountains would combine with intensive animal husbandry in the oasis areas,so as to improve the benefits.(2) In the upper cool oasis,which is 1 7002 600 m above sea level on the diluvial fan,the land product potentialities need to be further brought into full play.The light and heat conditions are suitable to plant spring wheat,potato,bean,rapeseed,garlic and fruit tree,and to develop intensive animal husbandry mainly.(3) In the middle oasis,which lies on middle and lower diluvial fan and alluvial plain,and is 1 1001 700 m above sea level,it is appropriate to develop water saving and land saving agriculture,to ex tend economic crops' areas,such as beetroot,cotton,hops,vegetables and melon and fruit with fine quality,and to popularize rearing livestock in pens energetically.(4) In the lower oasis area of about 9501 100 m above sea level,which lies in lower reaches of the Heihe River,the utmost important thing is to protect environment against further environmental deterioration.In brief,the overall strategy of land resources exploitation in the Heihe area is to protect the upper reaches,develop the middle reaches and maintain the lower reaches.

Key words: Heihe River Basin, oasis, land resources, optimum disposition