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: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=678761
• 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且具有挑战性的科学任务。我的工作受到基本问题的推动：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，以及如何从海洋沉积物中可靠地提取古环境的定量信息。我的研究计划的长期目标是校准微化石（主要是甲藻包囊）作为沿海水域环境条件的生物代表，并推进第四纪晚期的高分辨率（古）环境重建。更具体地说，我的研究基于有机壁微生物的识别：主要是甲藻包囊，以及沉积物中的花粉、孢子和有孔虫有机内壁。这些微化石在沉积物中保存完好，其记录包含沉积时的环境条件信息，可用于研究现在和过去地质时期的海面状况、海洋环流、气候和海洋初级生产力。 ****该研究计划旨在详细分析美国和加拿大太平洋沿岸多个地理位置的甲藻包囊沉积记录。它利用了维多利亚大学已建立的古环境实验室的设施，以及我的小组成员和合作者在过去几年中收集的大量沉积样本。未来五年我的研究主要目标是：1）调查不同程度的气候变化如何影响不列颠哥伦比亚省（BC）沿海水域以及温哥华岛和北加州边缘地区的浮游植物组成和初级生产力； 2）对初级生产力和海面条件的近期和前人类趋势进行高分辨率定量重建； 3) 绘制海洋沉积物中记录的过去约 50,000 年主要和次要气候事件的时间和强度图，特别强调全新世。****拟议的工作将提供高分辨率的水文时间序列以及基于甲藻包囊记录的北太平洋东部气候变化。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，第四纪晚期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汇模型非常重要。 **