李海军　崔一娇　任永强　姜媛　崔瑜　吴芮欣　王树芳

摘 要：为研究地表水对地下水的涵养效果，以2020年永定河春季生态补给过程为例，分析了永定河补水期间河道沿岸126眼地下水观测井的水位与水质等数据。研究结果显示，永定河生态补水2个月后，第四系地下水位上升区面积超过了450 km2，基岩地下水位上升区面积超过190 km2。受含水介质类型和河道过水量及水头的影响，基岩水的上升幅度最大可接近24 m，远远大于第四系地下水的升幅。地表水补给地下水后，地下水中的重碳酸盐和硝酸盐氮的浓度有所下降。永定河春季生态补水对沿岸地下水补给量约9800万m3。

关键词：永定河;生态补水;地下水涵养;水位响应

Analysis on the effect of ecological water replenishment of  Yongding River in spring 2020 on groundwater conservation in Beijing

LI Haijun1， CUI  Yijiao2， REN  Yongqiang1，  JIANG  Yuan1， CUI  Yu1， WU Ruixin2， WANG Shufang2

（1. Beijing Institute of Geology， Beijing 100195， China; 2. Beijing Institute of Hydrogeology and Engineering Geology

（Beijing Institute of Geological Environment Monitoring）， Beijing 100195， China）

Abstract： In order to study the effect of surface water on groundwater conservation， the water level and quality data of 126 groundwater observation wells along the Yongding River were analyzed during the ecological water replenishment period in the spring of 2020. The results show that after 2 months of replenishment， the Quaternary groundwater level rising area exceeded 450 km2， and the bedrock groundwater level rising area exceeded 190 km2. Affected by the type of water-bearing medium， as well as the flow volume and the water head， the maximum increase of the bedrock groundwater level can be close to 24 m， which is far greater than that of the Quaternary groundwater. After surface water replenished， the Bicarbonate and Nitrate nitrogen content in the groundwater decreased . The spring ecological replenishment of the Yongding River recharged approximately 98 million m3 of water to the aquifers along the River.

Keywords： Yongding River; ecological water replenishment; groundwater conservation; water level response

北京西部為太行山脉，北部为燕山山脉，地势西北高、东南低，东南是缓缓向渤海倾斜的由永定河、潮白河冲洪积物形成的平原，形象地称为“北京湾”。永定河流出山地进入“北京湾”后，因地势平缓，流速降低，河流携带的砾石、泥沙便在出山口后以扇形堆积下来，形成冲洪积扇，从扇顶到扇缘地势逐渐变低、沉积物颗粒逐渐变细。永定河出山以后，在平原上漫流摆动，形成不同历史时期的河道自北向南分别为古清河、古高梁河和古水（北京市文史研究馆，2016），3000年前北京地区最早的城市——蓟城建立在永定河故道沿岸，永定河被称为是北京的母亲河。由于自然环境变化和水资源过度开发，永定河北京平原段出现全年断流，地下水位持续下降（高飞等，2019;白鹏等，2018）。……