Oxygen-18 in different waters in Urumqi River Basin
The variations of the stable oxygen isotope in different water mediums in Urumqi River Basin, China, are analyzed. The stable oxygen isotope in precipitation has marked temperature effect either under synoptic or seasonal scale at the head of Urumqi River. The linear regression equations of δ18O against temperature are δ18O=0.94T-12.38 and δ18O=1.29T-13.05 under the two time scales, respectively. The relatively large δ18O/temperature slopes show the strong sensitivity of δ18O in precipitation to temperature variation at the head of Urumqi River. According to the analyses on the δ18O in precipitation sampled at three stations with different altitudes along Urumqi River, altitude effect is notable in the drainage basin. The δ18O/altitude gradients have distinct differences: the gradient from Urumqi to Yuejinqiao is merely -0.054‰/hm, but -0.192‰/hm from Yuejinqiao to Daxigou, almost increasing by 2.6 times over the former. No altitude effect is found in surface firn in the east branch of Glacier No.1 at the head of Urumqi River, showing that precipitation in the glacier is from the cloud cluster with the same condensation level. Influenced by strong ablation and evaporation, the δ18O in surface firn increases with increasing altitude sometimes. Survey has found that the δ18O in meltwater at the terminus of Glacier No.l and in stream water at Total Control have the similar change trend with the former all smaller than the latter, which displays the different runoff recharges, and all mirror the regime of temperature in the same term basically.
Key wordsstable oxygen isotope temperature effect altitude effect
Unable to display preview. Download preview PDF.
- He Yuanqing, Yao Tandong, Yan Meixueet al., 2000. The new results of δ18O studies on the system of precipitation, snow-ice and glacial runoff at the Glacier Baishui No.1 region in Mt. Yulong, China.Journal of Glaciology and Geocryology, 22(4): 391–393. (in Chinese)Google Scholar
- He Yuanqing, Yao Tandong, Cheng Guodonget al., 2001. Climatic records in a firn core from an alpine temperate glacier on Mt. Yulong, southeastern part of the Tibetan Plateau.Episodes, 24(1): 13–18.Google Scholar
- Hou Shugui, Qin Dahe, Li Zhongqinet al., 1998. Present environmental processes of ice core δ18O records of the No.l Glaciers at the headwater of Urumqi River, Xinjiang, China.Geochimica, 27(2): 109–116. (in Chinese)Google Scholar
- Hou Shugui, Qin Dahe, Ren Jiawen. 1999. Re-examination on the climatological significance of the ice core δ18O records from the No.l Glacier at the head of Urumqi River.Geochimica, 28(5): 438–442. (in Chinese)Google Scholar
- Liu Fengjing, Williams M, Cheng Guodonget al. 1999. Hydrochemical process of snowmelt water in Urumqi River, Tianshan Mountains.Journal of Glaciology and Geocryology, 21(3): 213–219. (in Chinese)Google Scholar
- Moser H, Stichler W. 1980. Environmental isotopes in ice and snow. In: Handbook of Environmental Isotope Geochemistry (1). Amsterdam-Oxford-New York: Elsevier Scientific Publishing Company, 141–178.Google Scholar
- Saxena R K, Eriksson E, 1985. Hydrometeorological interpretation of isotopic data on atmospheric moisture and precipitation.Annals of Glaciology, 7: 181–184.Google Scholar
- Yao Tandong, Sun Weizhen, Pu Jianchenet al., 2000. Characteristics of stable isotope in precipitation in the inland area-a case study of the relation between δ18O in precipitation and temperature in Urumqi River, China.Journal of Glaciology and Geocryology, 22(1): 15–22. (in Chinese)Google Scholar
- Zhang Xinping, Nakawo M, Yao Tandonget al., 2002. Variations of stable isotopic compositions in precipitation on the Tibetan Plateau and its adjacent regions.Science in China (D), 45(6): 481–493Google Scholar
- Zhang Xinping, Yao Tandong, Nakawo M, 2001. Oxygen-18 in present-day precipitation on the Tibetan Plateau.Science in China (E), 44(supp): 41–47.Google Scholar