地理学报 ›› 2007, Vol. 62 ›› Issue (5): 510-517.doi: 10.11821/xb200705007

• 青藏高原气候 • 上一篇    下一篇

雅鲁藏布江流域降水中δ18O 的时空变化

刘忠方, 田立德, 姚檀栋, 巩同梁, 尹常亮, 余武生   

  1. 1. 中国科学院青藏高原研究所, 北京100085; 2.中国科学院寒区旱区环境与工程研究所冰冻圈与环境联合重点实验室, 兰州730000; 3. 西藏水利规划勘测设计研究院, 拉萨 850000
  • 收稿日期:2007-01-17 修回日期:2007-03-23 出版日期:2007-05-25 发布日期:2010-08-04
  • 作者简介:刘忠方(1975-), 男, 山西临汾人, 在读博士, 主要从事青藏高原稳定同位素水文方面研究。 E-mail: liuzf406@126.com
  • 基金资助:

    国家自然科学基金项目(40121101; 40671043; 40571039); 国家基础研究发展规划(2005CB422002)中国科学 院重要方向项目(KZCX3-SW-339)

Variations of δ18O in Pr ecipitation of the Yar lung Zangbo River Basin

LIU Zhongfang, TIAN Lide, YAO Tandong, GONG Tongliang, YIN Changliang, YU Wusheng   

  1. 1. Institute of Tibetan Plateau Research, CAS, Beijing 100085, China; 2. Key Laboratory of Cryosphere and Environment, CAREERI, CAS, Lanzhou 730000, China; 3. Institute of Tibetan Water Resource Reconnaissance and Designing, Lhasa 850000, China
  • Received:2007-01-17 Revised:2007-03-23 Online:2007-05-25 Published:2010-08-04
  • Supported by:

    National Natural Science Foundation of China, No.40121101; No.40671043; No.40571039; National Basic Research Program of China, No.2005CB422002; Knowledge Innovation Program of CAS, No.KZCX3-SW-339

摘要:

通过研究2005 年西藏雅鲁藏布江流域拉孜、奴各沙、羊村和奴下4 个站点降水中的 δ18O变化, 揭示了雅鲁藏布江流域降水中稳定同位素的时空变化规律。研究显示, 雅鲁藏布 江流域降水中δ18O季节变化明显, 高值出现在季风降水之前的春季, 而低值出现在季风降水季节, 其间降水中δ18O具有明显的“降水量效应”; 从空间上看, 降水中的δ18O从下游至上游 递减, 造成这种分布特征主要是由于“高程效应”以及水汽远距离输送导致其中的18 被贫化的结果。经计算表明, 雅鲁藏布江流域降水中δ18O由于“高程效应” 造成的递减率为 0.34‰/100m, 而水平方向上自东向西由于水汽远距离输送造成的递减率为0.7‰/100km。从季风期间大范围的降水过程来看, 降水中δ18O的空间变化主要受“降水量效应”制约。

关键词: 雅鲁藏布江流域, δ18O, 降水, 时空变化

Abstract:

The paper reveals the temporal and spatial variations of stable isotope in precipitation of the Yarlung Zangbo River Basin based on the variations of precipitation δ18O at four stations (Lazi, Nugesha, Yangcun and Nuxia) in 2005. The results show that the δ18O of precipitation has distinct seasonal variations in the Yarlung Zangbo River Basin. The maximum value of δ18O occurs in spring prior to monsoon precipitation, and the minimum value occurs during monsoon precipitation. From the spatial variations, with the "altitude effect" and rainout process during moisture transport along the Yarlung Zangbo River valley, δ18O of precipitation is gradually depleted. Thus δ18O of precipitation reduced gradually from the downstream to the upstream, and the lapse rate of δ18O in precipitation is approximately 0.34‰/100m and 0.7‰/100km due to the two reasons. During monsoon precipitation, spatial variations of δ18O in precipitation is dominated by "amount effect" in the large scale synoptic condition.

Key words: Yarlung Zangbo River Basin, *18O, precipitation, temporal and spatial variations