Abstract: It is with “dryness” K=0.16εt/r that the area of arid -lands including Tarim Basin, Zunggar Basin, KumuI-Turpan Basin in Xinjiang, Hexi Cor-ridor in Gansu, Alxa Region in Inner Mongolia and Ningxa, and Qaidam Basin in Qinghai is deter mined.
The arid areas are poor in water resources: the first consideration for exp1oiting the arid areas should be to the quantity and distribution of wa-ter resources; and the utilization of water resources should be combined with the protection of ecological envinoument. Preseu1ly, the eco1ogical environmet of arid areas is grievously devasted, so more attention shou1d be paid to it.
Since 1ate Tertiary period, the natural environment in arid regions of our country tends to be turned drier, which has been proved by sedimentary stratum. The climatic change in human historical period is with feature of waving. The influence of human activities towards the natural env ironment become so great that it should be considered serious1y in exp1oiting the arid regions. The way of using without control the Nature is not desirable.