Riverbank filtration has a very important role in the supply of drinking water globally. However, this water source is vulnerable, because rivers are easily contaminated. To assess its vulnerability, it is essential to understand the properties of the aquifer including the sources of the water and the transit time. Therefore, a comprehensive investigation of the Hungarian Danube River-‘riverbank’ system was conducted on two of its islands (Szentendre and Csepel). Water level, temperature and electrical conductivity were monitored in the wells located in the riverbank, and water samples were collected regularly from the wells and the river for stable hydrogen and oxygen isotope analyses over a year. It was found that the wells located at different distances from the Danube River have various responses to the hydrological changes occurring in the river. Transit time distributions (TTD) belonging to different production wells were determined by the lumped parameter method, based on the convolution integral. Differences in the TTDs of the wells are explained by their distance from the Danube River, spatial variations in the aquifer hydraulic properties and the varying pumping rates. Additionally, the estimated mixing ratio of different water sources (i.e., Danube River and background shallow groundwater infiltrated from precipitation) to the exploited water suggests that the contribution of precipitation is less than 20 %.

中文翻译：

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稳定同位素和水文地质测量：对多瑙河河岸系统中穿越时间和混合比的影响


河岸过滤在全球饮用水供应中发挥着非常重要的作用。然而，这种水源很脆弱，因为河流很容易受到污染。要评估其脆弱性，必须了解含水层的特性，包括水的来源和穿越时间。因此，匈牙利多瑙河的“河岸”系统在其两个岛屿（圣安德烈和谢佩尔）进行了全面调查。监测位于河岸的井中的水位、温度和电导率，并定期从井和河流中收集水样，以便在一年内进行稳定的氢氧同位素分析。研究发现，位于多瑙河不同距离的井对河流中发生的水文变化有不同的响应。属于不同生产井的渡越时间分布 （TTD） 由基于卷积积分的集总参数法确定。井 TTD 的差异可以通过它们与多瑙河的距离、含水层水力特性的空间变化和不同的抽水速率来解释。此外，不同水源（即多瑙河和降水渗入的背景浅层地下水）与已开采水的估计混合比表明，降水的贡献小于 20 %。