塔克拉玛干沙漠浅层地下水位对单井抽水的响应过程研究

Response process of shallow groundwater level to single well pumping in Taklimakan Desert

为了研究人工抽水行为对周边地下水位的影响,在塔里木沙漠公路防护林生态工程第69号水源井处布设了抽水试验观测场,利用连续定位观测数据,分析了地下水位降深与时间的关系、地下水位的空间差异性规律;在此基础上利用Neuman井流模型方法,分析了含水层的传导性和贮水性,确定了该区域的相关水文地质参数;并利用Theis预报方法,对抽水引起的水位变化进行了短期预报。研究结果表明:抽水过程水位上升和下降过程均可分为快速和慢速两个阶段,含水层具有弹性释水和重力释水作用的特征;计算得出部分水文地质参数为:T=1.50E+1m3/d,Kh=3.74E+1 m/d,σ=1.12E-2;预测得出持续抽水1000 min时的抽水影响半径约为400m。文中研究所得出的水文地质参数符合该地区的水文地质条件,可作为相似区域水文地质学研究的参考;地下水位在抽水行为结束后,能够恢复到抽水前的水平;抽水行为对周边地下水位的影响范围不大,多个水源井之间不会形成相互干扰,不会引起天然地下水位的持续下降。研究结果可为沙漠公路沿线地下水资源的可持续利用和防护林生态工程整体的稳定性及长久运行提供一定的理论依据。

In order to study the effects of pumping on the groundwater level, we set up aquifer test observation site in No. 69 water supply well for the shelter forest engineering. Relationship between water level drawdown and time and space variation law of water table were analyzed by continual localization observed data. The aquifer conductibility, store characteristics and regional hydrogeology parameter were determined by Neuman well flow model. Using the Theis model, a method for the short term forecast of the groundwater level variation was pres ented. The results showed that both water level rise and drop in the process of pumping water were able to di vided into fleet and sluggish phases. The aquifers took on elasticity release and gravitation release characteris tics. The calculated hydrogeological parameter is T = 1.50E ＋ 1 m3/d, Kh = 3.74E ＋ 1 m/d, or = 1.12E 2 and radius of influence of pumping water was about 400 meters when pumping 1000 minutes. The result was in a greement with the conditions of actual hydrogeological and groundwater resources exploitation, and could be a reference for the hydrogeological research in other similar area. The research recognized the groundwater level could have recovered to pre pumping levels when the pumping water stopped. The range of influence of pum ping water is relatively small and groundwater level persistent decline is not truth for lift irrigation of ecological engineering along the Tarim Desert Highway sheherbelts, which provides datum basic for sustainable using of groundwater resource and steady function of shelterbelts ecological engineering.