Dissertation Research: Paleovegetational Response to Volcanism: Eocene/Oligocene Lower Cedarville Flora, California

论文研究：古植被对火山作用的反应：始新世/渐新世下塞达维尔弗洛拉，加利福尼亚州

• 批准号: 9520826
• 负责人: Richard Fisher
• 金额: --
• 依托单位: University of California-Santa Barbara
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-08-01 至 1998-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9520826&HistoricalAwards=false
• 关键词: Dissertation; Research; Paleovegetational; Response; Volcanism

9520826 Fisher At numerous sites in northern California, Oregon, and Washington, volcanic deposits preserve ancient vegetational types and make possible the critical analysis of trends in plant species replacement and habitat change through time. Graduate student Jeffrey Myers under the guidance of Professor Richard Fisher at the University of California-Santa Barbara is studying deposits of Eocene and Oligocene age, ca. 30 million years old, in the West, to assess vegetational changes across a broad region of the landscape over a relatively short span of geological time. The goal is to distinguish between a single, major secular shift in vegetation (moist humid tropical to seasonal temperate forest) or a more complex mosaic pattern of local habitat types. Numerous deposits of the same age will be visited and sampled, and their major plant components identified; a critical aspect of the research is to incorporate modern analyses on post-depositional processes (so-called taphonomic processes like decay and local transport by water or by animals) so ensure that fossil deposits accurately reflect local vegetation. Interest in global climate change and its environmental effects reinforces the need for fine-scale analysis of the fossil record. The Eocene-Oligocene focus of the proposed research emphasizes a time of global cooling, with resulting shifts in temperate-zone vegetation. How and over what timescales the vegetation changes in species composition are major unresolved questions in paleontology, to which this research brings a rigorous taphonomic approach.

在北方加州、俄勒冈州和华盛顿的许多地点，火山沉积物保存了古老的植被类型，并使人们有可能对植物物种更替和栖息地随时间变化的趋势进行批判性分析。加州大学圣巴巴拉分校研究生杰弗里·迈尔斯（Jeffrey Myers）在理查德·费舍尔（Richard Fisher）教授的指导下，正在研究大约始新世和渐新世时代的沉积物。在西方，它有3000万年的历史，以评估在相对较短的地质时间内，在一个广阔的景观区域内的植被变化。其目的是区分单一的，主要的长期变化植被（潮湿潮湿的热带季节性温带森林）或更复杂的镶嵌模式的地方生境类型。将访问和采样许多相同年龄的沉积物，并确定其主要植物成分;研究的一个关键方面是纳入对沉积后过程（所谓的埋藏过程，如腐烂和水或动物的局部运输）的现代分析，以确保化石沉积准确反映当地植被。对全球气候变化及其环境影响的关注加强了对化石记录进行精细分析的必要性。拟议研究的始新世-渐新世重点强调全球变冷的时间，导致温带植被的变化。植被在物种组成上如何变化以及变化的时间尺度是古生物学中尚未解决的主要问题，这项研究带来了严格的埋藏方法。