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Water resources in arid areas of economic and social development of resource constraints, arid areas of competitive water use has evoked a variety of conflicts, serious impact on regional stability, security and development. Meanwhile, irrational human activities take up too much water, making the already fragile arid environment deteriorating. To the limited water resources in arid zones rational allocation, maintenance of ecosystem healthy development, we must first understand the exact distribution of water resources and changes. This paper selected as the study area Heihe River, is a typical inland river Tail area, very little precipitation, non-zonal vegetation line and totally dependent on groundwater survive, rely mainly on groundwater recharge Heihe runoff. Over the past decades, due Heihe River region's population growth, industrial and agricultural development, water consumption increases, the study area lakes have dried up, a large area of ??dead vegetation. Based on the geological and hydrogeological investigation and a lot of water on the basis of observational data, select 1990 to 1999 10 years of observational data, on a monthly time step, combined with GIS technology and FEFLOW groundwater flow simulation software, groundwater in the study area numerical simulation, and make short-term forecasting, on this basis, the use of wild vegetation - groundwater relationships survey data to simulate vegetation growth under water stress conditions. Preliminary get the following results: 1. In aid of GIS software, based on drilling data, the establishment of three-dimensional space in the study area aquifer system and hydrogeological models, on this basis, to establish a three-dimensional groundwater flow model, using FEFLOW finite element groundwater modeling software, completed the groundwater flow numerical model calibration, simulation and forecasting. 2. The main recharge of groundwater sources river infiltration, evaporation is the main excretion pathway. Overall, the study area, groundwater recharge and discharge in a negative equilibrium. 3.1990 years, the study area there was a downward trend in the overall groundwater level, but the change was smaller, the interannual variability of groundwater level in the upstream water mainly by the impact of the study area itself is small industrial and agricultural water consumption, groundwater bit little impact. 4. During the study area groundwater obviously change the maximum amount of change within a year up to 4m. This is due to the amount of water in the middle is not evenly distributed throughout the year. 5. The growth of vegetation in the study area mainly affected groundwater coercion, use of field survey data to establish the study area typical vegetation cover and water table depth mathematical relationship obtained by the analog out of the study area is typical of groundwater potential distribution of vegetation. The results show that, although a few years into the policy reasons, Heihe downstream release of water has increased, but is still in negative equilibrium groundwater, although the decline is small, but over time, the water table will gradually decrease. Therefore, in order to ensure stability of the downstream groundwater level, the release of water to the downstream Heihe still increasing.
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