【作者】 边文英；

【导师】 王旭升；

【作者基本信息】 中国地质大学（北京） ， 地下水科学与工程， 2011， 硕士

【摘要】 全球约三分之一的陆地位于干旱和半干旱地区,而且世界上近一半国家都不同程度受到干旱缺水问题的困扰。我国也不例外,尤其是西北地区干旱缺水问题尤为突出。位于黑河下游的额济纳盆地是典型干旱区内陆河流域和生态环境脆弱区。额济纳盆地由于深居我国西北内陆腹地,为典型的大陆性干旱气候区,降水稀少,蒸发强烈,因此地下水主要通过蒸发蒸腾作用而做无效损耗,但是地下水是黑河下游额济纳绿洲维持和人民生产、生活的主要用水来源,因此地下水大量的通过蒸发蒸腾而损耗,对黑河下游的绿洲维持和当地的社会经济发展造成很大的困扰。黑河下游地区地下水的主要来源是通过黑河水流的季节性渗漏来补给。但是近几十年来随着中游地区张掖绿洲面积的不断扩大,过度放牧,用水量逐年增加,使得上中游向下游的泄水量减少,从而造成下游用水量不足,绿洲萎缩、湖泊干涸、植被退化和沙漠化等一系列生态环境问题。因此根据黑河下游降水稀少,蒸发强烈的典型气候特征和地下水的补排情况,本文针对性的提出研究干旱区傍河地下水蒸发型动态的问题。而且本文没有采取一般的大尺度进行地下水位动态模拟,而是在额济纳盆地范围内选取了两条符合条件的傍河的典型剖面进行小尺度、微观上的地下水位动态的模拟与分析。本文首先系统介绍了额济纳盆地大尺度上的自然地理概况、水文地质条件、地下水的补排情况和地下水与植被的关系等;然后根据研究区的自然地理特征、含水层结构和地下水的赋存情况,确定研究区的数学模型为源汇项只包括蒸发蒸腾的一维潜水流模型;并分别对其稳定流模型和非稳定模型进行求解和计算,得到了在线性蒸发条件和非线性蒸发条件下一维稳定流的解析解;对典型剖面进行动态模拟,并对动态识别结果进行讨论和分析,得出典型剖面的年水位振幅随距河道距离的变化曲线,以及地形对年水位振幅最敏感地段变化的影响。更多还原

【Abstract】 One third of world lands are located in arid and semi-arid areas, and nearly half of the countries in the world are obsessed with the drought and water shortage problems. Besides China, the drought and water shortage problems seem like outstanding in the Northwest Region.The Ejina Basin which is located at the Lower Reaches of the Heihe River is?the typical Inland River Basin in Arid Regions and fragile ecological environment Regions. Because the Ejina Basin is located in Hinterland of the Northwestern China, and it is belong to continental monsoon climate area, which is rare precipitation and strong evaporation.? So most of the groundwater is lost invalidly by the evapotranspiration. But the groundwater is the recharge sources for maintaining the Ejin oasis,producting and living by people in the lower reaches of Heihe River. So maintaining the Ejin oasis at the Lower Reaches of the Heihe River and the local social and economic development are obsessed with the most of the evapotranspiration loss.?The groundwater in lower Heihe River region is recharged by the seasonal leakage of the Heihe. In recent decades, as the area of Zhangye Oasis in the middle reaches of the expansion, overgrazing and water consumption increasing every year make the upper and middle reaching downstream of the vent water decrease, and result in the lack of water downstream, shrinking oasis, lakes dried up, vegetation degradation and desertification and a series of ecological and environmental problems.Therefore, under the typical climate characteristics of the Rare precipitation, strong evaporation at the Lower Reaches of the Heihe River and the typical relationship between the recharge and discharge, this paper points out the question that The simulation and analysis on evaporation-dynamic of groundwater in Arid zone riverside .But this did not take the general conduct of large-scale dynamic simulation of groundwater level, it takes small-scale, micro-dynamics of the groundwater level simulation and analysis for the two typical profiles which are selected in Ejina basin. Firstly, this paper describes the natural geographical of the Ejina Basin systemly on a large scale, hydrogeological conditions, groundwater recharge and discharge conditions and the relationship between groundwater and vegetation. Then according to the natural geographical features, aquifer structure and occurrence of groundwater of the study area, we determine the mathematical model of the study area which is one-dimensional diving flow model including evapotranspiration; and to solve and calculate the steady-model and the transient-model, to get the analytical solutions of the one-dimensional steady-model under the linear and nonlinear evaporation. Finally, simulate the groundwater-dynamic of the typical profile, discuss and analysis the recognition results; obtain the curves of the amplitude versus level with the distance from the river and the amplitude of topography on the impact of water.更多还原