The Study Of Optimized Use Of Water Resources In Yin-chuan Basin

Yin-chuan basin is situated in arid areas of northwestern China, the water resources there is scarce and eco-environment is vulnerable. With the development of economy and increase of population, the demand for water resources in the basin increases progressively. Water shortage has been an important factor affecting the development of society and economy in Yin-chuan basin. Furthermore, because of the lack of environmental protection and scientific management in the exploitation of water resource, as well as the unreasonable exploitation pattern, some eco-environmental problems have been occurred. Therefore, in combination of the whole development plan of the basin, exploiting the water resources in accordance with the society, economy and environment, setting up the optimized water resource development model, making the exploitation of water resources and the development of society and economy in a harmonized mode are several momentous tasks in the reasonable exploitation of water resources in Yin-chuan Basin.The premise of optimizing the development of water resources in a region is making a thorough assessment its amount. The amount of surface water in Yin-chuan basin is clear, but up to now, the groundwater resource in the basin has never been thoroughly assessed. Therefore, on the basis of brief summarization of geography, society and economy of Yin-chuan basin, the hydrogeological condition was stated and analyzed, the groundwater resource was assessed using balancing method. Results showed the quality of phreatic water in Yin-chuan basin is bad and can be easily contaminated, it is not suitable for water supply of industry and living. While the quality of confined groundwater is good and not easy to be polluted, it is the ideal supply water for industry and living. The groundwater resource in Yin-chuan basin is relatively rich, the total amount of groundwater in the basin is 21.4456x108m3/a, the exploitable amount of groundwater in the basin is 16.4967x108m3/a.Through the analysis of development status of water resources and expoitation problems, the paper pointed out the surface water resource in Yin-chuan basin is Yellow river water mainly used for agricultural irrigation. Although the development degree of groundwater in the basin is low, but because of lack of reasonable plan, the groundwater in some areas has already been over-exploited. Problems existing in the development of water resources in Yin-chuan basin are: Surface water, groundwater, water for city use and water for agriculture use as well as water for ecological use are not reasonably programmed, leading to the waste of water resources and occurrence of salted soil. At the same time, because of the large amount drainage of wasted water, solids and gas as well as the comprehensive use of chemical fertilizer, the groundwater was polluted in different degree, the range and extent of the pollution have a tendency to increase yearly. Whether the water is used in industry or in agriculture, the wasteof water is very serious, the technology of water usage is slow, and the production value of water is low.According the problems existing in the development of water resources in Yin-chuan basin, aimed at sustainable exploitation of water resources and harmoniously development of society, economy and environment, the optimized water resource use and management model was set up based on the rules of combined use of surface water and groundwater, improving the eco-environment, saving the use of water and elevating production value of water use. The calculated results of the model indicated that from year 2000-2020, the groundwater usage keeps a tendency of increase, while the amount of water introduced from Yellow river is decreasing. This result is not only in favor of improving the eco-environment of Yin-chuan basin, keeping the sustainable development of society and economy, but also play an important role in solving the problem of drying up of Yellow river in downstream areas. On the basis of this, countermeasures for sustainable wa...