| 引用本文: | 王君波,朱立平,鞠建廷,谢曼平,汪勇.西藏普莫雍错不同岩芯环境指标的对比研究及其反映的近200年来环境变化.湖泊科学,2009,21(6):819-826. DOI:10.18307/2009.0611 |
| WANG Junbo,ZHU Liping,JU Jianting,XIE Manping,WANG Yong.Environmental changes reflected by a comparative proxy study among multiple cores from Pumoyum Co, Tibet in the last 200 years. J. Lake Sci.2009,21(6):819-826. DOI:10.18307/2009.0611 |
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| 摘要: |
| 在西藏南部普莫雍错不同位置处采集了四支岩芯沉积物,对其中一支利用210Pb和137Cs方法建立了沉积物的年代序列,并对其他三支岩芯的上部沉积物进行了总有机碳、无机碳、粒度及化学元素含量的分析.结合沉积物年代,对不同岩芯的环境代用指标进行对比,讨论了该地区近200年来的环境变化状况.结果表明,不同位置处采集的岩芯其环境指标变化趋势在整体上具有一定的可比性,但在细节变化与环境指标的数值上仍具有明显的差异,显示了湖泊内部沉积状况的空间差异性,这可能是由于采样点水深、水下地形以及与主要补给河流距离的不同而造成的.PY04岩芯环境指标显示普莫雍错湖区环境在约1900AD之前较为稳定;在约1900-1940AD之间湖区环境波动加剧,地表侵蚀增强,沉积速率加快;湖区环境在1940AD左右发生了明显的变化,温度显著升高,沉积物粒度增大,湖泊处于退缩状态,表明湖泊环境向暖干化方向发展. |
| 关键词: 湖泊沉积物 多岩芯 环境变化 普莫雍错 青藏高原 |
| DOI：10.18307/2009.0611 |
| 分类号: |
| 基金项目:国家自然科学基金项目(40871099,40571172)资助 |
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| Environmental changes reflected by a comparative proxy study among multiple cores from Pumoyum Co, Tibet in the last 200 years |
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WANG Junbo1, ZHU Liping1, JU Jianting2, XIE Manping1, WANG Yong1
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1.Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100085, P.R.China;2.Science in China Press, Beijing 100717, P.R.China
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| Abstract: |
| Four sediment cores were collected at three sites from Pumoyum Co, Southern Tibet. Sedimentation age was constructedby using 210 Pb and137Cs measurements from one short core. Environmental proxies such as total organic carbon, inorganic carbon,grain size and element concentrations were analyzed for upper parts of other three cores. The proxies from different cores werecompared and then environmental changes during the last ca. 200 years were discussed. Although proxies changing trends of differentcores are similar, obvious differences appear in both detailed variations and proxies values, probably resulting from different waterdepth, underwater landform conditions and distances to rivers among the sites. Environment condition in this area was stable before1900AD, but it fluctuated during 1900-1940AD with enhancement of surface erosion and increased sedimentation rate. Remarkablechanges took place at about 1940AD, showing that the temperature increased greatly, grain size of sediments became coarser and thelake was in the state of shrinkage, indicating environment in this area changed to a warm/dry state. |
| Key words: Lake sediment multiple cores environmental changes Pumoyum Co Tibetan Plateau |
