Late Quaternary environmental and climatic changes in the eastern North Pacific

北太平洋东部晚第四纪环境和气候变化

• 批准号: RGPIN-2015-06388
• 负责人: Pospelova, Vera
• 金额: $ 1.6万
• 依托单位: University of Victoria
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=662482
• 关键词: Late; Quaternary; environmental; climatic; changes

Understanding of mechanisms behind climate change, and its influence on Earth's ecosystems is an important and challenging scientific task. My work is motivated by fundamental questions: how changing climate impacts coastal environments, how past abrupt climatic changes affected marine primary productivity, and how to reliably extract quantitative information on paleoenvironments from marine sediments. The long-term objective of my research program is to calibrate microfossils (primarily dinoflagellate cysts) as biological proxies of environmental conditions in coastal waters, and to advance high-resolution (paleo) environmental reconstructions in the late Quaternary. More specifically, my research is based on the identification of organic-walled microscopic organisms: primarily dinoflagellate cysts, as well as pollen, spores, and foraminiferal organic linings in sediments. These microfossils are well preserved in sediments, and their records contain information about environmental conditions at the time of deposition, which will be used to investigate sea-surface conditions, ocean circulation, climate, and marine primary productivity both now and in the geological past.****This research program aims at the detailed analysis of dinoflagellate cyst sedimentary records from a multitude of geographic locations along the Pacific coast of USA and Canada. It utilizes facilities of the established Paleoenvironmental Laboratory at the University of Victoria, and immense wealth of sedimentary samples collected over the last few years by members of my group and collaborators. The main objectives of my research over the next five years are: 1) to investigate how the climate changes of different magnitude affect phytoplankton composition and primary productivity in coastal waters of British Columbia (BC) and along the margins of Vancouver Island and northern California; 2) to make high-resolution quantitative reconstructions of recent and pre-anthropogenic trends in primary productivity and sea-surface conditions; and 3) to map the timing and magnitude of the major and minor climatic events over the last ~50,000 years recorded in marine sediments, with particular emphasis on the Holocene.****The proposed work will offer high-resolution time series of hydrographic and climate variability in the eastern North Pacific based on dinoflagellate cyst records. This will contribute to our understanding of natural and human induced environmental changes, as well as marine ecosystem responses to these changes. In addition, quantitative reconstructions of marine primary productivity in the late Quaternary are very important for calibration of existing and future models of global climatic changes and carbon sequestration.**

了解气候变化背后的机制及其对地球生态系统的影响是一项重要而具有挑战性的科学任务。我的工作动机是基本问题：气候变化如何影响沿海环境，过去的气候突变如何影响海洋初级生产力，以及如何可靠地从海洋沉积物中提取有关古环境的定量信息。我的研究计划的长期目标是校准微体化石（主要是甲藻孢囊）在沿海沃茨的环境条件的生物代理，并推进高分辨率（古）环境重建在第四纪晚期。更具体地说，我的研究是基于有机壁微生物的鉴定：主要是甲藻孢囊，以及花粉，孢子和沉积物中的有孔虫有机衬里。这些微体化石在沉积物中保存完好，它们的记录包含了沉积时环境条件的信息，这些信息将用于研究现在和过去地质时期的海面条件，海洋环流，气候和海洋初级生产力。这项研究计划的目的是详细分析的甲藻孢囊沉积记录从众多的地理位置沿着美国和加拿大的太平洋沿岸。它利用了维多利亚大学古环境实验室的设施，以及我的团队成员和合作者在过去几年中收集的大量沉积样品。未来五年的主要研究目标是：1）研究不同程度的气候变化如何影响不列颠哥伦比亚省（BC）沿海沃茨和温哥华岛沿着边缘及北方加州的浮游植物组成和初级生产力; 2）对初级生产力和海表条件的近期和人类活动前的趋势进行高分辨率的定量重建; 3）绘制海洋沉积物中记录的过去5万年来主要和次要气候事件的时间和幅度，特别强调全新世。拟议的工作将根据甲藻孢囊记录提供北太平洋东部水文和气候变化的高分辨率时间序列。这将有助于我们了解自然和人类引起的环境变化，以及海洋生态系统对这些变化的反应。此外，晚第四纪海洋初级生产力的定量重建对于校准现有和未来的全球气候变化和碳固存模型非常重要。