The Water Resources System and Water Utilization in the Arid Northwest of China

Abstract

Water resources exploitation and sustaining development of arid and semi-arid area are among the most important global environment problems. One third of the total earth surface is arid or semi-arid, and in China, this area amounts to 47.5%. Water system in arid area has the following characters: total water resources shortage, poor recharges, distribution unbalance, evaporation playing a key role in water cycle, river and connected aquifers forming a uniform system, shallow groundwater having certain present recharge but deep groundwater usually having no recharge with the evidence of very low tritium detected. A series of environment deterioration problems, such as desertification, salinization of soil and groundwater, have risen during water resources exploitation because the ecosystem is rather weak. To realize the reasonable utilization of water resources in the arid area, we need to manage water resources in a scope of catchment, to control the oasis scale according to the water capacity of systems, to keep reasonable ecosystem water level, and to construct water saving society.