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塔里木河(塔河)是中国最长的内陆河,沿塔克拉玛干沙漠控制着新疆大部分地区.塔河自大西子水库以下已经断流30多年,引发许多严重的生态环境问题.为缓解下游的生态压力,向下游进行了几次紧急生态输水,以检验输水对塔河下游地区环境问题的影响.本文依据塔河下游的水文地质特征和极端干旱的气候条件,建立了不存在源汇项条件下的一维非稳定流模型并引入了傅里叶变换求解方法.通过对河流水位的阶梯状概化,简化了非稳定流模型的边界条件.为了查明区内含水层的结构,考虑到高密度电法兼具电测深和电剖面的特点,在研究区实施了一条高密度电法剖面.电法剖面揭示,区内潜水含水层呈水平层状分布,平均厚度约为35m.根据电法剖面的结果,经过实测资料验证,模型反演得到的潜水水位的最大平均绝对误差为0.3m,远远小于区内潜水水位波动的幅度.相关性分析表明,模型计算值和实测值之间具有显著的相关性.因此,模型很好的刻画了塔河下游河道附近地下水对上游输水的响应,为评价塔河下游生态输水的环境效应提供了一个有力的理论工具.
The Tarim River (Tahe) is the longest inland river in China and controls most parts of Xinjiang along the Taklimakan Desert. The Tahe River has been shut off for more than 30 years since the Zixizi Reservoir, triggering many serious ecological and environmental problems. Ecological pressure and conducted several emergency ecological water conveyance to the downstream to test the impact of water conveyance on the environmental problems in the lower reaches of the Tarim River.Based on the hydrogeological characteristics of the lower reaches of the Tarim River and the extreme drought climatic conditions, One-dimensional unsteady flow model is introduced and the Fourier transform method is introduced.The boundary conditions of the unsteady flow model are simplified by the stepwise generalization of the river water level.In order to find out the structure of the aquifer , Taking into account the characteristics of both the electrical sounding and electrical profiling of high-density electrical method, a high-density electrical method profile was implemented in the study area.The electrical profile revealed that the submerged aquifer in the area was horizontally layered with an average thickness of about 35m.According to the results of electrical sectioning, the maximum average absolute error of the submersible water level obtained from the model inversion is 0.3m, which is far less than the amplitude of the submerged water level in the area after verified by the measured data. It shows that there is a significant correlation between the model calculated value and the measured value.Therefore, the model well characterizes the response of the groundwater near the lower reaches of the Tarim River to the upstream water conveyance, and provides the basis for evaluating the environmental effects of the ecological water conveyance in the lower Tarim River A powerful theoretical tool.