Evaluation And Resolution Of Groundwater Resources Of The Yellow River In Shaanxi Province

Durative aridity, decreasing runoff and human activity have intensely affected groundwater system since 1980's, which resulted in changes such as dynamic field and chemical field, distribution on time-space and composition of groundwater. Under this condition, we need re-evaluate water resources in order to provide scientific evidence to maintain the restorability of groundwater in the Yellow river drainage.Therefore, supported by one of the national emphasis foundation research programming items, which studies on alteration rule of the restorable ability of groundwater in the Yellow river drainage (G1999043606), based on geological and hydrogeological conditions, we evaluate water resources of the Yellow river from the point of factors that affect the form of groundwater. The results show that natural resources of groundwater(84.04 108m3/a) and allowable withdrawal of groundwater (43.24 108m3/a)have changed greatly. We demonstrate the credibility of the evaluation results by compare it with different evaluation results from different departments in different stages.On the basis of research mentioned above, we analyse groundwater resources from the point of composing and influencing factors of groundwater. The results show that, compared with human activity, it is precipitate water which accounts for from 84 percent to 93 percent of the total recharge that mainly affects the form of groundwater in loess plateau of northern Shaanxi, however, the situation changes in Guanzhong basin, north to Wei river the chief factors that affect the form of groundwater is precipitate water and irrigation, whose amount occupy 84.6 percent of total recharge, while south to Wei river, 5.1 percent of total recharge comes from precipitate water and river leakage which are chief control factors of the form of groundwater compared with irrigation (19.2 percent). From these, we can conclude that the composition of groundwater are variant in different area, which results in difference of groundwater distribution on space.We analyse the rainfall sequence , runoff flux, base flow and dynamic data of groundwater in the whole research area, which show that the groundwater resources tend toward decreasing, especially from 90's on, groundwater resources fall down sharply while groundwater recharge is 76.7 percent of average annual recharge.Based on analyzing problems of development and exploitation of water resources in Shaanxi of the Yellow river drainage, we put forth the countermeasures to rationally develop and utilize regional water resources, thus successfully realize sustainable use of water resources and benign circulation of eco-environment according to the principle such as combination of surface water and groundwater , adaptation to local conditions,constructing the good and wiping the bad, exploring water sources and saving water, rational development and synthetical utilization. The research contents of the paper directly make up those of "973" term. The research results not only offer scientific evidence to rational exploitation and optimization allocation of water resources, but also provide reference value to development of water resources in arid and semiarid area of the west.