【摘要】 石羊河流域下游地区蒸发强度大、地下水循环速度慢,加之近年来地表水供给量的严重不足,过度开采地下水已引发了区域性地下水位下降、植被退化、盐渍化、沙漠化等一系列生态环境问题的不断恶化。地下水位的下降与矿化度的增高存在着明显的正相关性,特别是流域下游地区地下水矿化度的增高趋势明显。根据影响地下水动态的主要影响因素可将石羊河流域地下水的动态类型划分为蒸发型、开采型、径流开采型、渗入型和蒸发开采型5种,在此基础上,结合多年地下水位和水质变化的实测资料,对石羊河流域地下水下降趋势和亏空状况进行模拟分析,表明该区近40a来地下水位持续下降,亏空量不断增加,并且具有明显的加速趋势。1960年武威和民勤盆地地下水亏空量为1 74×108m3,1998年已达4 52×108m3,如不采取有力措施加以治理,预计2010年将达到6 7×108m3,这将对该区生态环境产生严重的影响。更多还原

【Abstract】 Due to the strong evaporation and slow circulation rate of the groundwater, together with serious shortage of the surface water supply and overuse of the groundwater resources in recent years in the lower reach of Shiyang river basin, the environment here has suffered from a series of eco\|environmental problems such as the lowering groundwater table, vegetable degeneracy, land salinization and desertification, etc. If no effective measures are taken, the deterioration of the eco\|environment of this vast area will be unavoidable. There is an eminent positive correlation between the lowering of the groundwater table and the increasing water mineralization, especially in the lower reach area, the increasing tendency of groundwater mineralization is extremely clear. According to the main controls on groundwater dynamic status, the dynamic types of the groundwater in Shiyang river basin can be classified into five types, that is, evaporation type, exploitation type, runoff\|exploitation type, infiltration type and evaporation\|exploitation type. Based on these studies and in combination with the measured data on groundwater table and water quality in Shiyang River over a long term, the lowering trends and shortage status of the groundwater in the study area have been simulated. As a result of simulation, it can be seen that the groundwater table is continuously lowering in nearly forty years and the shortage of groundwater is steadily rising, which also shows an accelerating tendency in recent years. In 1960, the groundwater shortage of Wuwei and Minqing basins was 1\^74×108  m3, and this figure reached 4\^52×108  m3 in 1998. If such a situation continues, it is predicted that this figure will be up to 6.7×108  m3 in 2010, implying that the eco\|environment here will be influenced seriously.更多还原