Extinction and Recovery in Terrestrial Ecosystems across the Permian-Triassic Boundary in South Africa

南非二叠纪-三叠纪边界陆地生态系统的灭绝和恢复

• 批准号: 0230024
• 负责人: Conrad Labandeira
• 金额: --
• 依托单位: Smithsonian Institution
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-02-01 至 2008-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0230024&HistoricalAwards=false
• 关键词: Extinction; Recovery; Terrestrial; Ecosystems; across

PROJECT ABSTRACTEXTINCTION AND RECOVERY IN TERRESTRIAL ECOSYSTEMS ACROSS THE PERMIAN-TRIASSIC BOUNDARY IN SOUTH AFRICAEAR-0230024PIs: Hallie J. Sims, Marion K. Bamford, and Conrad C. LabandeiraThe Permian/Triassic (P/Tr) boundary 252 million years ago is recognized as the largest mass extinction in the history of marine life. The terrestrial fossil record indicates that there was widespread and elevated turnover in plants and insects during this interval, but interpretation of the event has been hindered by the apparent lack of a continuous terrestrial sequence spanning the boundary. The Permian and Triassic compression floras in Karoo Basin of South Africa record a temporal series of snapshots of local vegetation, and thus provide a model system to assess extinctions and ecological restructuring in plant communities across the boundary. In addition, the diversity and frequency of insect herbivory in these communities is preserved as damage on fossil leaves, wood, seeds, and other reproductive organs and can be used to assess patterns in plant-insect interactions. PIs project combines examination of specimens in museum collections and new field work to bulk collect plant macrofossils from 23 Karoo localities spanning the P/Tr boundary. Palynological analysis will allow them to integrate the sites with current geochronological information, including new radiometric dates and known vertebrate biozones in the Karoo. The work will allow PIs to test hypotheses related to changes in the composition and relative abundance within plant communities. By integrating quantitative data on plants and their associated insect herbivores, this research will help understand how terrestrial life responded to the most devastating extinction in the Phanerozoic by providing the first rigorous assessment of changes in ecosystems across the P/Tr boundary at multiple trophic levels.

南非二叠纪-三叠纪界线上陆地生态系统的灭绝和恢复-0230024 PI：Hallie J.西姆斯，Marion K. Bamford和Conrad C. 2.52亿年前的二叠纪/三叠纪（P/Tr）界线被认为是海洋生物历史上最大的大规模灭绝。 陆地化石记录表明，在这段时间内，植物和昆虫的周转率普遍提高，但由于明显缺乏跨越边界的连续陆地层序，对这一事件的解释受到了阻碍。 南非卡鲁盆地的二叠纪和三叠纪挤压植物群记录了当地植被的时间序列快照，从而提供了一个模型系统，以评估跨越边界的植物群落的保护和生态重建。 此外，在这些社区的昆虫植食性的多样性和频率被保存为化石叶，木材，种子和其他生殖器官的损害，并可用于评估植物-昆虫相互作用的模式。 PI项目结合了对博物馆收藏标本的检查和新的野外工作，从跨越P/Tr边界的23个卡鲁地区大量收集植物宏体化石。孢粉学分析将使他们能够将这些地点与当前的地质年代学信息结合起来，包括新的放射性测定日期和卡鲁已知的脊椎动物生物区。 这项工作将允许PI测试与植物群落内的组成和相对丰度变化有关的假设。 通过整合植物及其相关的昆虫食草动物的定量数据，这项研究将有助于了解陆生生物如何应对中生代最具破坏性的灭绝，并通过提供对多个营养级P/Tr边界生态系统变化的第一次严格评估。