Multi-isotopic molecular records of rapid African terrestrial vegetation changes

非洲陆地植被快速变化的多同位素分子记录

• 批准号: 5430091
• 负责人: Dr. Enno Schefuß
• 金额: --
• 依托单位: Zentrum für Marine Umweltwissenschaften (MARUM)
• 依托单位国家: 德国
• 项目类别: Emmy Noether International Fellowships
• 财政年份: 2004
• 资助国家: 德国
• 起止时间: 2003-12-31 至 2006-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/5430091?language=en
• 关键词: Multi; isotopic; molecular; records; rapid

The aim of the proposed research is to investigate the response of the African vegetation on rapid climatic fluctuations during the Honocene and the last Glacial. Abrupt changes in the tropical hydrological cycle linked with high-frequent climate variations of the high latitudes have been detected. However, the actual response of the terrestrial biosphere on the millennialscale environmental changes is yet unknown. Investigations of sediment cores around Africa allow the reconstruction of rapid changes in the low-latitude climate system. I propose to utilise novel molecular-isotopic techniques to identify and characterise rapid terrestrial vegetation changes. Ultra-highresolution (decadal to centennial) plant lipid-accumulation records from marine sediment cores will be established with the recently available Gas chromatography/Time-of-flight mass spectrometer (GC/TOF-MS) at Woods Hole Oceanographic Institution. Accompanying high-resolution plant lipid-specific stable carbon and hydrogen isotope records will supply detailed climatic information. The timing of the signal transfer from the continent to the sediments will be investigated by compoundspecific radiocarbon dating of terrigenous lipid fractions. With molecular-isotopic analyses of aerosol samples eolian transport processes will be characterised.

拟议研究的目的是调查非洲植被对全新世和末次冰期气候快速波动的反应。热带水文循环的突变与高纬度地区频繁的气候变化有关。然而，陆地生物圈对千年尺度环境变化的实际响应尚不清楚。对非洲周围沉积物岩芯的调查可以重建低纬度气候系统的快速变化。我建议利用新的分子同位素技术来识别和监测快速的陆地植被变化。伍兹霍尔海洋研究所将利用最近可用的气相色谱/飞行时间质谱仪（GC/TOF-MS）建立海洋沉积物岩心的超高分辨率（十年至百年）植物脂质积累记录。伴随着高分辨率的植物脂质特定的稳定碳和氢同位素记录将提供详细的气候信息。信号从大陆转移到沉积物的时间将由化合物特定的陆源脂质组分的放射性碳测年法进行研究。通过对气溶胶样本的分子同位素分析，将描述风成输送过程的特征。