玉符河外源回灌对岩溶地下水影响研究

为缓解济南市的泉水保护与城市供水矛盾，玉符河先后实施了多期地表水回灌补源地下水工程，对维持泉水持续喷涌下城市正常取用地下水起到了重要作用。外源水水质与当地岩溶水差异明显，长期回灌将对岩溶水产生一定影响。针对这一问题，以2021—2022年玉符河的回灌补源为例，利用同位素试验和水化学综合分析等多种手段相结合的方式，研究玉符河流域岩溶水受外源水补给的影响，分析影响区内地下水水化学特征及其组分的变化趋势。结果表明：玉符河回灌对岩溶水有一定的补给作用，根据其补给的程度将研究区分成三个区带，在河岸东侧Ⅰ区范围内河流入渗补给占50%以上，是主要的影响区；城区泉群位于Ⅲ区内，水质受玉符河补源影响有限，但水位会有一定的抬升。
自玉符河至Ⅲ区，水化学类型由SO₄·Cl-Na·Mg型逐渐向HCO₃-Ca·Mg型过渡，由于兴济河的调水补源，泉群地下水类型又转变为HCO₃·SO₄-Ca·Mg型。影响区内岩溶水各离子含量变化主要是河水与岩溶水的物理混合引起，同时伴随着水岩平衡的改变。补源经过一个水文年后，各离子逐步接近原来含量水平。研究成果为科学实施玉符河回灌补源提供了依据，对促进保泉与供水的有机统一具有一定意义。

Study on the influence of external recharge of Yufu river on karst groundwater

Jinan is famous for its abundant spring water resources, but with the advancement of urbanization, the ground continues to harden, resulting in a significant reduction of the area effectively supplying karst water, and hence a sudden decrease in water supply. The decrease has seriously threatened the continuous gushing of spring water in Jinan. At the same time, the urban population is constantly rising, so is the demand for water supply. The contradiction between spring water protection and urban water supply is becoming increasingly serious.
In order to alleviate the contradiction in Yufu river, the projects in which groundwater was recharged by surface water were completed in different phases. In these projects such as the water discharge project of the Wohushan reservoir, the project of converting surface water into groundwater, and the Jinan City project of the East Line of the South-to-North Water Diversion Project, the surface water from the Wohushan reservoir, the Yuqing lake reservoir, and the Yangtze River has been respectively used for the recharging. They play an important role in maintaining the continuous gushing of spring water for the normal use of groundwater in cities.