ABSTRACT The north-east of Iran is a semi-arid region and faces a water shortage crisis. Therefore, monitoring water resources using accurate methods such as stable isotopes technique is vitally important. In this study, precipitation events were sampled in 10 stations in the Mashhad basin and the Bojnourd region in 2008, 2009, 2011, and 2015, additional surface and groundwater. These samples were analysed at the Ottawa University for both oxygen and hydrogen isotopes. In addition, the moisture sources were determined using the backward trajectories of the HYSPLIT model. The backward trajectories showed that both high- and low-latitude water bodies provide moisture for the north-east of Iran. However, the role of high-latitude water bodies including the Caspian, the Black, and the Mediterranean Seas is stronger. On the other hand, the stable isotopes showed large variations and the developed meteoric water lines deviated in both slope and intercept from the global meteoric water line. This showed that the precipitation events of the north-east of Iran were provided by various air masses and moisture sources. Finally, plotting the isotope values of the surface water resources on high- and low-latitude meteoric water lines demonstrated that these water resources were dominantly recharged by precipitation events originating from high-latitude water bodies.

中文翻译：

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伊朗东北部水汽源δ18O和δ2H特征及其在地表水补给中的作用

摘要伊朗东北部是半干旱地区，面临缺水危机。因此，使用稳定同位素技术等准确方法监测水资源至关重要。在这项研究中，2008 年、2009 年、2011 年和 2015 年在马什哈德盆地和 Bojnourd 地区的 10 个站点对降水事件进行了采样，增加了地表水和地下水。这些样品在渥太华大学进行了氧和氢同位素分析。此外，水分来源是使用 HYSPLIT 模型的后向轨迹确定的。后向轨迹表明，高纬度和低纬度水体都为伊朗东北部提供水分。但里海、黑海、地中海等高纬度水体的作用更强。另一方面，稳定同位素显示出较大的变化，发达的大气水线在斜率和截距上都偏离了全球大气水线。这表明伊朗东北部的降水事件是由各种气团和水分来源提供的。最后，在高纬度和低纬度大气水线上绘制地表水资源同位素值表明，这些水资源主要由源自高纬度水体的降水事件补给。