ABSTRACT

Iran is a semi-arid and arid country which always faces a water shortage crisis. Thus, the water resources in Iran should be studied by accurate methods such as stable isotope techniques. In precipitation sampling stations across Iran, the δ¹⁸O (ranges from −16.3 to −0.3 ‰, −4.9 ‰ average), δ²H (−114 to –13 ‰, −24.2 ‰ average) and d-excess (−2.1 to –22.7, 16.5 ‰ average) values are higher compared to δ¹⁸O (ranges from −10.9 to −3.1 ‰, −6.7 ‰ average), δ²H (−71 to −6 ‰, −37.4 ‰ average) and d-excess (1.0 to –21.6 ‰, 14.9 ‰ average) values in groundwater stations. Stable isotope distribution maps in precipitation and groundwater were also developed for Iran. The stepwise technique was used to study the role of parameters influencing stable isotopes in Iran precipitation. Results show the dominant role of temperature, elevation and latitude as well as ‘cP and MedT’ air masses mixture on stable isotope values in precipitation. Furthermore, the contribution percentage of each air mass which influences Iran in groundwater resources recharge was studied using ‘Simmr’ package in R programming language. Finally, the accuracy of the developed stable isotope distribution maps was validated.

摘要

伊朗是一个半干旱和干旱的国家，始终面临缺水危机。因此，应通过稳定同位素技术等准确方法研究伊朗的水资源。在伊朗各地的降水采样站，δ ¹⁸ O（范围从 -16.3 到 -0.3 ‰，-4.9 ‰ 平均值）、δ ² H（-114 到 –13 ‰，-24.2 ‰ 平均值）和d -excess (-2.1 to –22.7, 16.5 ‰ 平均值）值高于δ ¹⁸ O（范围从 -10.9 到 -3.1 ‰，-6.7 ‰ 平均值），δ ² H（-71 到 -6 ‰，-37.4 ‰ 平均值）和d- 地下水站的超量值（1.0 到 –21.6 ‰，14.9 ‰ 平均值）。还为伊朗开发了降水和地下水中的稳定同位素分布图。逐步技术用于研究影响伊朗降水中稳定同位素的参数的作用。结果显示温度、海拔和纬度以及“cP 和 MedT”气团混合物对降水中稳定同位素值的主导作用。此外，使用R编程语言中的“Simmr”包研究了影响伊朗的每个气团在地下水资源补给中的贡献百分比。最后，验证了所开发的稳定同位素分布图的准确性。