基于环境同位素技术的再生水灌区水循环特征解析

A Study of Water Cycle in Reclaimed Water Irrigation District with Isotopic

摘要: 再生水灌区水源包括再生水、地表水、地下水等，准确、客观的表征再生水灌区各水源之间的相互转换关系是开展多水源联合调度保障灌区用水安全和提高水资源利用率的关键。本研究采用环境同位素和水化学成分作为平原灌区水循环研究的示踪剂，揭示了灌区水循环特征。结果表明，灌区地表水和地下水之间存在强烈的水力联系，整个灌区的补给排泄关系主要是地表水补给地下水，人工抽取河道再生水灌溉农田产生深层渗漏，补给地下水是导致灌区地下水电导率明显波动变化的主要原因，同位素分析结果显示灌区再生水、地表水和地下水均呈现出强烈的蒸发浓缩作用，地表再生水对地下水的补给从北到南逐渐减弱。

Abstract: In reclaimed water irrigated district, the water resources characteristic with synthetic reclaimed water, stream water, ground water and so on. It is essential for security and efficiency utilization of reclaimed water to precisely assess the transformation among different water bodies in reclaimed water irrigation district. This study uses isotopic and hydrochemical data of water samples to quantity study the regional water cycle. It has shown that there is intense hydraulic connection between surface water and ground water. Most ground water is recharged from surface water. The reclaimed water irrigation is one of most important way for reclaimed water recharged to groundwater and results in obvious unstable variation of EC. The results of ground water isotopic composition showed an intense evaporation-concentration process during recharge from precipitation and surface water. The ground water isotopic concentration gradually decreases from Northwest to Southeast and results by decrease of surface water recharge to ground water.