Reasonable Distribution Of Water Resources And The Strategy To Water Crisis In Shiyanghe Valley

The scarcity of water resource, overdrafting of groundwater caused the ecological environment worsening day by day in the Shiyanghe valley. In order to solve the problem of water crisis and environment deterioration,it is necessary to study on the reasonable distribution of water resources and the strategy to water crisis in the Shiyanghe valley.In this paper,the evolution and formation of water resources in Shiyanghe valley was discussed from remote, modern to contemporary times, through the runoff curve from 1956 to 2000, trend and characteristics of 8 rivers from 1980 to 2003, and the changes of groundwater level in different region in Minqin. The dynamics and future trends of surface water and groundwater wase analyzed.The main natural and contrived factors cadse the shortage of water resource in Shiyanghe valley.Geography,weather,precipitation,evaporation are the main natural reasons, population increase,economic growth, unreasonable industrial structure,water pollution, unreasonable distribution of water resources and low use efficiency are the main contrived factors which lead to the overdrafting of groundwater and water crisis.In 2000,there is still a gap between water supply and demand in Shiyanghe valley,the shortage amount is 8.28×108m3,and the shortage degree is 29.2%.In the future,it is predicted that the gap between water supply and demand is still existing.To 2010,the shortage amount is 5.696×108m3,and the amout of overdrafting groundwater is 2.880×108m3. To 2020,the shortage amount is 3.881×108m3, and the amout of overdrafting groundwater is 2.411×108m3. And to 2030, the shortage amount is 5.873×108m3, and the amout of overdrafting groundwater is 2.487×108m3.But it is hopeful that the relative balance between total water supply and total water demand will be reached through the project of the South-to-North water transfers.At the same time,the conception of existing water resources has been advanced, which is a innovation in china. It incloudes using existing water,living existing water, development existing water. Throuh the caculation, it can be conclude that the existing water for assuring the basic needs, being well off , modernized is unsustainable.Through the distribution of water resource in Shiyanghe valley by population,land use,GDP. It can be conclude that distribution is unreasonable. So the alloction model has been advanced to solve this problem,which was based on AHP.The objected level uses efficient water use ,the criterion level use economic B1,social life B2,environment B3,technology and managemant B4,and the evelvation level use 19 index. At last, the valley is divided to 4 districts Liangzhou D1,Gulang D2,Minqin D3,Jinchang D4.Using the results of score by experts,to the distribution amount was obtained for each city.The strategy for water crisis ware suggesfed apply agricutral water saving, reconstruct large irrigation distrigh,wake industry and tertiary industry water saving, change the industrial structure, control water pollution , promote clean production,improre input system,reform water price, unify manage water resource,set up water saving society etc.Through the analysis on economic benefits of water saving and water tranfer, effects of treatment,the distribution will be move reasonable and ecological environment will be improred.