SHE Yuanyang1,2,3, WANG Shengjie4,5, WANG Peng2,3, LEI Shijun4,5, YANG Lei1
（1.School of History Culture and Tourism, Longnan Teachers College, Longnan 742500, China;
2.School of Geography and Environment, Jiangxi Normal University, Nanchang 330022, China;
3.Key Laboratory of Poyang Lake Wetland and Watershed Research, Ministry of Education, Jiangxi Normal University, Nanchang 330022, China;
4.College of Geography and Environmental Science, Northwest Normal University, Lanzhou 730070, China;
5.Key Laboratory of Resource Environment and Sustainable Development of Oasis of Gansu Province, Lanzhou 730070, China）
Abstract：In order to investigate the basic characteristics of stable hydrogen and oxygen isotopes in precipitation in the Western Qinling Mountains, 109 precipitation samples were collected in Longnan of Gansu from January to December 2020. The intra-annual variations of stable hydrogen and oxygen isotope ratios and their influencing factors were analyzed, and the connection between precipitation isotopes and moisture sources were studied using the HYSPLIT model. The results showed that the weighted averages of δ18O and δ2H in precipitation were ?11.0‰ and ?74.1‰, respectively. The heavy isotopes in precipitation were depleted in rainy season (δ18O=?11.5‰ and δ2H=?79.0‰) and enriched in non-rainy season (δ18O=?9.0‰ and δ2H=?55.1‰). The local meteoric water line was δ2H=8.1δ18O+14.6, and the slope and intercept of this local equation were higher than the global mean. The amount effect was detected for δ18O, and there was no temperature effect. The rainy season with depleted precipitation isotopes was significantly impacted by the monsoon moisture, and the westerlies all year round brought limited precipitation to the study area. This study is helpful to improve the knowledge of precipitation isotopes evolution in the Western Qinling Mountains and to understand the controlling regimes of precipitation isotopes, which may provide references to the modern hydrometeorology and paleoclimate studies.
Key words：Western Qinling Mountains; stable hydrogen and oxygen isotopes; d-excess; extreme precipitation; moisture source
EARTH AND ENVIRONMENT Vol.51, No.2, Tot No.352, 2023, Page 143
