Tracing groundwater-surface water sources and transformation processes in the Ba River Basin through dual isotopes and water chemistry

• Published in: Applied geochemistry Vol. 176; p. 106199
• Main Authors: Zhao, Weijie, Qian, Hui, Xu, Panpan, Yang, Shuhan, Liu, Yixin, Shen, Yanjun, Zang, Yongqi, Wang, Qiming, Cao, Zhiming
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.12.2024
• Subjects: alkalinity; atmospheric precipitation; Ba River Basin; cation exchange; Dual isotope; geochemistry; Groundwater; Hydrochemical characterization; hydrochemistry; hydrogen; multivariate analysis; oxygen; pollution control; rivers; Surface water; water management; watersheds; Hydrochemical characterization; Groundwater; Dual isotope; Surface water; Ba River Basin
• ISSN: 0883-2927
• DOI: 10.1016/j.apgeochem.2024.106199

The interactions between groundwater and surface water, including their recharge dynamics and proportional contributions, are crucial for the hydrological cycling, water resource management, and pollution control. This study focused on the Bahe River basin, employing methods such as the Gibbs diagrams, the multivariate statistical analysis, and the MixSIAR model to analyze the hydrochemical parameters and the hydrogen-oxygen isotopes of both groundwater and surface water to quantitatively analyze the transformation relationships between water bodies. The results indicated that both the groundwater and surface water in the research area exhibited weak alkalinity, with the groundwater primarily characterized by HCO3–Ca·Na and surface water predominantly by HCO3–Ca. Furthermore, the geochemical evolution was predominantly affected by the rock weathering and the cation exchange processes. The distribution characteristics of hydrogen and oxygen isotopes in groundwater and surface water suggested that the atmospheric precipitation constituted the main source of recharge in the Bahe River basin. According to the MixSIAR model, the upstream groundwater contributed 90.1% to the surface water, with 9.9% attributed to the atmospheric precipitation. In the midstream, the atmospheric precipitation and groundwater contributed 21.9% and 78.1%, respectively, to the surface water. Downstream, the groundwater contributed significantly to the surface water (78.5%), whereas atmospheric precipitation contributed 28.5%. This study could provide a foundation for understanding the sources and evolution of groundwater and surface water, thereby promoting the effective management and utilization of groundwater resources. [Display omitted] •The sources of hydrochemical constituents in groundwater and surface water are elucidated.•The mechanism of water-rock interaction of surface water and groundwater is clarified.•The connection between groundwater and surface water is revealed by hydrogen and oxygen isotopes analysis.•The conversion between surface water and groundwater is quantitatively determined using MixSIAR model.