State Key Laboratory of Biogeology and Environmental Geology & MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences, Beijing 100083, China; School of Water Resources and Environment, China University of Geosciences, Beijing 100083, China.
State Key Laboratory of Biogeology and Environmental Geology & MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences, Beijing 100083, China; School of Water Resources and Environment, China University of Geosciences, Beijing 100083, China.
Sci Total Environ. 2020 Oct 20;740:140163. doi: 10.1016/j.scitotenv.2020.140163. Epub 2020 Jun 12.
Knowledge of groundwater discharge (location and sources) into Poyang Lake is needed for water resources management and ecological security. In this study, hydrochemical and stable (δD and δO) and radium (Ra, Ra, Ra, and Ra) isotopic approaches were employed to study the hydrochemical and isotopic characteristics of groundwater and surface water (river water and lake water) to identify the places where groundwater discharged into Poyang Lake and the groundwater discharge sources. The results showed that the groundwater discharge area was extensive during the dry season. The locations of predominant groundwater discharge were indicated by the evolution of radium and stable isotopes in lake water along two water flow profiles. At the confluence of Ganjiang and Xiushui rivers, groundwater with more negative δO value than that of the lake water discharged into this area, and the estimated groundwater discharge proportion in this area was close to that of the river water input. The main sources of groundwater input for Poyang Lake were inferred to originate from clastic rock pore-fissure aquifer and bedrock fissured aquifer around this lake. This study also found that groundwater affected by the anthropogenic activities may have discharged into Poyang Lake. Future studies are required to focus on groundwater discharge into Poyang Lake for its management and protection.
了解地下水向鄱阳湖的排泄（位置和来源）对于水资源管理和生态安全至关重要。本研究采用水化学和稳定（δD 和 δO）以及镭（Ra、Ra、Ra 和 Ra）同位素方法，研究了地下水和地表水（河水和湖水）的水化学和同位素特征，以确定地下水排入鄱阳湖的地点和地下水的排泄源。结果表明，旱季地下水排泄区广泛。在两个水流剖面中，根据湖水镭和稳定同位素的演化，指示了主要地下水排泄的位置。在赣江和修水的交汇处，地下水的 δO 值比湖水的更负，估计该地区的地下水排泄比例接近河水的输入。鄱阳湖地下水的主要补给源推断来自该湖周围的碎屑岩孔隙裂隙含水层和基岩裂隙含水层。本研究还发现，受人类活动影响的地下水可能已排入鄱阳湖。未来的研究需要集中在地下水排入鄱阳湖的管理和保护上。
