引用本文: | 刘颖,孙惠玲,周晓娟,段立曾,李华勇,张虎才.过去5000 a以来抚仙湖沉积物有机质碳同位素的古环境指示意义.湖泊科学,2017,29(3):722-729. DOI:10.18307/2017.0322 |
| LIU Ying,SUN Huiling,ZHOU Xiaojuan,DUAN Lizeng,LI Huayong,ZHANG Hucai.Paleoenvironmental significance of organic carbon isotope in lacustrine sediments in Lake Fuxian during the past 5 ka. J. Lake Sci.2017,29(3):722-729. DOI:10.18307/2017.0322 |
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过去5000 a以来抚仙湖沉积物有机质碳同位素的古环境指示意义 |
刘颖1,2, 孙惠玲1,2, 周晓娟1,2, 段立曾1,2, 李华勇1,2, 张虎才1,2
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1.云南师范大学旅游与地理科学学院 昆明 650500;2.云南师范大学高原湖泊生态与全球变化重点实验室 昆明 650500
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摘要: |
通过测定抚仙湖沉积物全有机样品的稳定碳同位素组成(δ13Corg)、总氮、总有机碳含量指标并计算碳氮比值,对过去5000 a以来抚仙湖沉积物有机质来源、δ13Corg的影响因素及其所指示的古环境意义进行分析.结果表明:在过去的5000 cal a BP里,抚仙湖沉积物有机质主要来源发生明显变化,沉积物有机质输入由内源水生生物和陆生C3植物共同输入(5000-2300 cal a BP阶段)转变为以内源沉水植物、浮游植物和藻类等输入为主(2000 cal a BP至今阶段);有机质来源发生变化是造成抚仙湖沉积物δ13Corg值变化的主要原因;2000 cal a BP以来,陆源有机质输入的锐减与人类活动的影响密切相关;在2300-2000 cal a BP阶段,抚仙湖沉积物δ13Corg值的快速变化可能指示了抚仙湖流域的古环境在这一时期经历了快速变化的气候事件. |
关键词: 抚仙湖 稳定碳同位素 碳氮比值 有机质来源 古环境 |
DOI:10.18307/2017.0322 |
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基金项目:国家自然科学基金项目(41201203);云南省高端人才引进项目(2010CI111);湖泊沉积与环境变化云南省创新团队项目(2010CI) |
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Paleoenvironmental significance of organic carbon isotope in lacustrine sediments in Lake Fuxian during the past 5 ka |
LIU Ying1,2, SUN Huiling1,2, ZHOU Xiaojuan1,2, DUAN Lizeng1,2, LI Huayong1,2, ZHANG Hucai1,2
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1.College of Tourism and Geography Science, Yunnan Normal University, Kunming 650500, P.R.China;2.Key Laboratory of Plateau Lake Ecology & Global Change, Yunnan Normal University, Kunming 650500, P.R.China
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Abstract: |
We measured several indexes including the stable organic carbon isotope (δ13Corg), the total nitrogen content, the total organic carbon content and the ratio of carbon and nitrogen content of bulk sediments in Lake Fuxian to exploring the sources of organic matters in sediments and the paleoenvironmental significance of δ13Corg during the last 5 ka. The results showed the organic matter inputs from both the terrestrial C3 plants and the aquatic organisms as the main source to the lake sediments have greatly changed during the period of 5000-2300 cal a BP, and changed to the only aquatic input (submerged plants, phytoplankton and algae) since 2000 cal a BP. δ13Corg values of bulk sediments in Lake Fuxian were mainly affected by different organic matter inputs. Rapid changes of the δ13Corg values during the stage of 2300-2000 cal a BP may indicate that the paleoenvironment of Lake Fuxian basin has experienced a rapid climate event. |
Key words: Lake Fuxian stable carbon isotope carbon and nitrogen ratio organic matter source palaeoenvironment |