| 引用本文: | 沈吉,吴瑞金,安芷生.大布苏湖沉积剖面有机碳同位素特征与古环境.湖泊科学,1998,10(3):8-12. DOI:10.18307/1998.0302 |
| Shei Ji,Wu Rui-jin,An Zhi-sheng.Characters of the Organic 6 C and Paleoenvironment in the Section of Dabusu Lake. J. Lake Sci.1998,10(3):8-12. DOI:10.18307/1998.0302 |
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| 摘要: |
| 1994年9月，在吉林省大布苏湖湖盆东部，获取了总厚度为8．10m沉积剖面样品．以10cm间隔采样．对样品中有机质成分及稳定联同位素研究表明，沉积物中有机质主要来源于陆源高等植物，沉积物中有机物的δ13℃值指示了源生物的特征．在暖干时期，沉积物中有机质具有较高的δ13C值；反之，冷湿时期．沉积物中有机质的δ13C值降低，结合剖面碳酸盐含量及14C年代分析表明，湖区15000年来经历了多期冷湿与暖干的气候旋回，大约距今6700年左右，气候变干并进入稳定的温暖时期，湖水逐渐高度浓缩，形成了现今的盐碱湖。 |
| 关键词: 有机碳同位素 古气候 大布苏湖 |
| DOI：10.18307/1998.0302 |
| 分类号: |
| 基金项目:国家自然科学基金（49702028）;中国科学院湖泊专项课题资助项目 |
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| Characters of the Organic 6 C and Paleoenvironment in the Section of Dabusu Lake |
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Shei Ji1, Wu Rui-jin1, An Zhi-sheng2
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1.Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008;2.State key Laboratory of Loss and Quaternary Geology, Xi'an 730000
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| Abstract: |
| The organic materials in lake sediments mainly come from (1)autogenous materials (21)al lochthonous materials. As in the second case.the organic materials in sediments mainly come from the plants which were brought into the lake by flowing water,So the δ13℃ vaktes of the or ganic m aterials are controlled by the plants types.The values of δ13C of the organic materials l1 sediments can supply the information of w hat types of plants the organic materials come froln. According to the plallt types the paleoclimatic information Can he obtained, Aco rding to the verticaI distribution of the δ13C in Dabusu Lake.has been reconstructed the paleoclimate evolution of this region since 1 5000 years as fo[iows： 15400-14000 aB P (depth 8.10-7.30m )： the climate was cold and wet. During this stage there was a high lake level and stable environment. 14000 12200 aB P (depth 7,30-6,30m )：the climate was dry and tem perate. The Lake level descended rapidly, 1 2200-9500 aB P (depth 6,30-4,85m )：The climate was cold and wet, 9500-7800 aB P (depth 4.85～4,00m )：The climate came back to warm and dry.and Ihe lake Ieve1 was Iow. 7800～5500 aB P (depth 4.00-2,80m ) The temperature fell and the lake level rose.The climate was cooI and wet. Since 5500 aB P (depth 2.80-0m )：The climate bacame warm and dry. The Lake water condensed rapidly and finally the lake evolved into a saline hke. |
| Key words: Organic carbon isotope paleoclimate Dabusu Lake |
