δ2H and δ18O in Precipitation and Water Vapor Disentangle Seasonal Wind Directions on the Loess Plateau

In many areas of the Loess Plateau, groundwater is too deep to extract, making meteoric water (snow and rain) the only viable water resource. Here we traced the rainwater and water vapor sources using the δ2H and δ18O signature of precipitation in the northern mountainous region of Yuzhong on the Loess Plateau. The local meteoric water line in 2016 and 2017 was defined as δ2H = 6.8 (±0.3)∙δ18O + 4.4 (±2.0) and δ2H = 7.1 (±0.2)∙δ18O + 1.5 (±1.6), respectively. The temperature and precipitation amount are considered to be the main factor controlling the δ2H and δ18O variation of precipitation, and consequently, relationships were first explored between δ18O and local surface air temperature and precipitation amount by linear regression analysis. The temperature effect was significant in the wet seasons but was irrelevant in the dry seasons on daily and seasonal scales. The amount effect was significant in the wet seasons on a daily scale but irrelevant in the dry seasons. However, based on the data of the Global Network of Isotopes in Precipitation (GNIP) (1985–1987, 1996–1999) of Lanzhou weather station, the amount effects were absent at seasonal scales and were not useful to discriminate either wetter or drier seasons or even wetter or drier decades. Over the whole year, the resulting air mass trajectories were consistent with the main sources of water vapor were from the Atlantic Ocean via westerlies and from the Arctic region, with 46%, 64%, and 40% of water vapor coming from the westerlies, and 54%, 36%, and 60% water vapor from the north in spring, autumn and winter, respectively. In the summer, however, the southeast monsoon (21%) was also an important water vapor source in the Loess Plateau. Concluding, using the δ2H and δ18O signatures of precipitation water, we disentangled and quantified the seasonal wind directions that are important for the prediction of water resources for local and regional land use.

Авторы
Huang F.Q.1 , Song X.1 , Zhang Y.H.1 , Yang Q.F.1, 3 , Li F.M.1 , Wei J.Z.2 , Kuzyakov Y. 4, 5, 6
Издательство
MDPI AG
Номер выпуска
12
Язык
Английский
Статус
Опубликовано
Том
13
Год
2021
Организации
  • 1 State Key Laboratory of Grassland Agroecosystems|Institute of Arid Agroecology|School of Life Sciences|Lanzhou University
  • 2 Department of Agriculture and Rural Affairs of Gansu Province|Gansu Agricultural University
  • 3 Centre for Quantitative Biology|College of Science|Gansu Agricultural University
  • 4 Department of Soil Science of Temperate Ecosystems|Department of Agricultural Soil Science|University of Göttingen
  • 5 Agro-Technological Institute|RUDN University
  • 6 Institute of Environmental Sciences|Kazan Federal University
Ключевые слова
Isotopic approaches; Loess Plateau; Water vapor sources; δ<sup>2</sup>H and δ<sup>18</sup>O of precipitation
Дата создания
16.12.2021
Дата изменения
16.12.2021
Постоянная ссылка
https://repository.rudn.ru/ru/records/article/record/81341/
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