College of Water Sciences, Beijing Normal University, Beijing 100875, China.
China Irrigation and Drainage Development Center, Beijing 100054, China.
Int J Environ Res Public Health. 2022 Sep 26;19(19):12202. doi: 10.3390/ijerph191912202.
To better protect lacustrine ecologies and understand the evolutionary process of lake environments, it is critical to study the interacting mechanisms between lakes and the surrounding groundwater. The Wuliangsu Lake watershed is the largest wetland in the Yellow River basin and is the discharge area of the Hetao Irrigation District (HID), which is one of the three largest agricultural production areas in China. Due to the influence of human activities, the discharge water from the HID has led to the deterioration of the Wuliangsu Lake ecology and the degradation of the lake environment. Based on long-term observation data and water sampling data collected in 2021, a water-salt equilibrium model was used to analyze the recharge rate of groundwater to the lake. The contribution rate of groundwater to lake recharge in the study area was calculated with a Bayesian mixing model by combining D and O stable isotope data. Furthermore, the environmental evolutionary process of the lake was also analyzed using the collected water quality data. The results show that channel drainage was the main source of recharge to Wuliangsu Lake, accounting for more than 75%, while groundwater contributed less than 5% of lake recharge. After implementing the ecological water supplement plan, the concentration of various ions in the lake decreased, the concentration of the total dissolved solids (TDS) in the lake decreased from 1.7 g/L in 2016 to 1.28 g/L in 2021, and the ecological environment was improved. The contribution of groundwater to lake recharge was quantitatively analyzed. The results of this study can facilitate the development of vital strategies for preventing the further deterioration of lake water quality and for protecting wetland ecologies.
为了更好地保护湖泊生态系统，了解湖泊环境的演化过程，研究湖泊与周围地下水的相互作用机制至关重要。乌梁素海流域是黄河流域最大的湿地，也是中国三大农业生产区之一的河套灌区（HID）的汇水区。由于人类活动的影响，HID 的排水导致了乌梁素海生态恶化和湖泊环境退化。本研究基于 2021 年收集的长期观测数据和水样数据，利用水盐平衡模型分析了地下水对湖泊的补给速率。通过结合 D 和 O 稳定同位素数据，应用贝叶斯混合模型计算了研究区地下水对湖泊补给的贡献率。此外，还利用收集的水质数据分析了湖泊的环境演化过程。结果表明，河道排水是乌梁素海补给的主要来源，占比超过 75%，而地下水对湖泊补给的贡献不到 5%。实施生态补水计划后，湖泊中各种离子的浓度降低，总溶解固体（TDS）浓度从 2016 年的 1.7g/L 降低到 2021 年的 1.28g/L，生态环境得到改善。对地下水对湖泊补给的贡献进行了定量分析。本研究结果可以为防止湖泊水质进一步恶化和保护湿地生态系统提供重要的战略制定依据。
