ISSN 1000-3665 CN 11-2202/P

    “引哈济党”工程对敦煌盆地地下水位影响的数值模拟研究

    Numerical simulation studies of the influences of water transferring project from the Haerteng River to the Dang River on groundwater levels in the Dunhuang Basin

    • 摘要: 国务院批准的《敦煌水资源合理利用与生态保护综合规划(2011—2020)》旨在缓解敦煌盆地水资源的合理利用与生态保护之间的矛盾。随着规划的实施,近年来盆地内水面的面积增大,作为规划骨干工程之一的“引哈济党”工程的实施必要性得到质疑。地下水是盆地重要的水源,也是影响西湖自然保护区等生态的关键因素。为定量分析引哈济党工程不同调水量下盆地地下水位时空演化态势,本研究建立了地下水三维流数值模型,结合长期观测井和统测井水位等数据对模型进行了识别和验证。模型应用发现:2010—2018年区域年均地下水储量亏空约0.40×108 m3,主要分布于党河洪积扇区和党河灌区北部,但党河灌区和西湖自然保护区核心区的地下水储量亏空分别约2.62×106,9.99×106 m3。采用模型预测了调水量为0.80×108,0.90×108 ,1.00×108,1.20×108 m3/a时,50年后地下水位动态,发现党河洪积扇地下水位回升5.0~20.0 m,月牙泉区地下水位回升7.0~15.0 m,而西湖自然保护区在模拟期内地下水位回升0.5 m以内。地下水侧向径流补给是西湖自然保护区核心区的重要和持续的补给水源,“引哈济党”工程将确保西湖地下水位的缓慢回升。研究结果可为“引哈济党”工程的实施论证提供重要参考。

       

      Abstract: The objective of the Integrated Planning of Rational Water Resources Utilization and Ecological Protection (2011-2020) issued by the State Council is to relieve the contradiction of reasonable water resource utilization and ecological protection. After the implement of the planning in recent years, visible water area is added, and the necessities of the planning is doubted. Groundwater is an important water source, and is also one of key factors affecting the ecology in the Xihu Nature Protection Area. Aiming at an quantitative analysis of the tempo-spatial changes of groundwater levels under different transferred scenarios, this study establishes a three-dimensional groundwater flow numerical model, and calibrates and verifies the model using much data such as long-term observation well data and additional water level data obtained through field investigation. The model results show that groundwater storage in the study area is under a negative equilibrium state with a yearly average value of 0.04×108 m3, mainly distributed in the Danghe alluvial fan and the north part of the Dang River irrigation area. The yearly averaged groundwater storages in this irrigation area and the core region of the West Lake Protected Area have the decrement of 2.62×106 m3 and 9.99 ×106 m3, respectively. Scenarios analysis based on the different amount of water transferring project, which are 0.8×108 m3/a, 0.9×108 m3/a, 1.0×108 m3/a and 1.2×108 m3/a, are carried out by using the established model, and the results indicate that groundwater levels are increased around 5.0~20.0 m in the Danghe alluvial fan and 7.0~15.0 m in the Crescent Moon Spring area after 50 years. However, groundwater levels in the West Lake Protected Area has a slow increase trend of 0.5 m in the predication period. Subsurface runoff is important and sustainable recharge sources in the West Lake Protected Area, but the water transferring project may improve the slow recovery groundwater levels in the West Lake Protected Area. The results of this study will provide important references for argument of the implement of the water transferring project.

       

    /

    返回文章
    返回