Stable isotope characteristics of water resources in the coastal area of the Vietnamese Mekong Delta
Stable isotope characteristics of water resources in the coastal area of the Vietnamese Mekong Delta
复制标题
越南湄公河三角洲沿岸地区水资源稳定同位素特征
DOI：
10.1080/10256016.2019.1673746
复制
发表时间：
2019
影响因子：
1.3
通讯作者：
T. D.
中科院分区：
文献类型：
--
作者：
Tran;D,A.;Tsujimura;M.;Vo;L. P.;Nguyen;V. T.;Nguyen;L. D.;Dang;T. D.
氧和氢的稳定同位素可以为水的起源和水文过程提供有用的见解。本研究旨在调查越南湄公河三角洲沿海地区地下水和地表水的稳定H/O同位素特征。地表水的同位素和氯化物浓度显示出高度的季节性和线性空间变异性，这取决于到海洋的距离。上游流量和降雨的季节变化对同位素组成和氯离子浓度的变化起着重要作用。潮汐对地表水氯离子浓度也有影响，但不改变其同位素组成。蒸发对同位素组成的变化起着至关重要的作用，而淡水/海水混合对同位素变化的影响可以忽略不计。地下水的同位素组成和氯离子浓度具有空间异质性，反映了不同的补给来源和海水入侵过程。浅层地下水来源于降雨和地表水，蒸发损失小，与海水有不同程度的混合。深层含水层中的地下水可能在末次冰期通过开放地表水蒸发得到补给，海水入侵对这些含水层的影响很小。
The stable isotopes of oxygen and hydrogen can provide useful insights into water origin and hydrological processes. The present study aims to investigate the characteristics of stable H/O isotopes of groundwater and surface water in a coastal area of the Vietnamese Mekong Delta. Isotopes and chloride concentrations of surface water show a highly seasonal and linearly spatial variability, depending on the distance to the sea. The seasonal variation of upstream discharge and rainfall plays an important role in changes of the isotopic compositions and chloride concentrations. Tide also influences on chloride concentrations of surface water while it does not change the isotopic compositions. Evaporation plays a crucial role in changes of isotopic compositions, while the influence of freshwater/seawater mixing on isotopic variabilities is negligible. Groundwater has a spatial heterogeneity in isotopic compositions and chloride concentrations, reflecting different recharge sources and seawater intrusion processes. Groundwater in shallow aquifers originates from rainfall and surface water with small evaporative losses, and it experienced different magnitudes of mixing with seawater. Groundwater in deep aquifers might be recharged by open-surface water evaporation in the last glacial age with minor impacts of seawater intrusion on these aquifers.