Vegetation dynamics, paleoecology, and climate change during the Quaternary and Paleogene of Western Canada

加拿大西部第四纪和古近纪期间的植被动态、古生态和气候变化

• 批准号: RGPIN-2020-05026
• 负责人: Mathewes, Rolf
• 金额: $ 2.19万
• 依托单位: Simon Fraser University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2021
• 资助国家: 加拿大
• 起止时间: 2021-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=740358
• 关键词: Vegetation; dynamics; paleoecology; climate; change

The long-term goal of my research program is to reconstruct past environmental changes and their impacts on ecosystems, including human populations in British Columbia. Information provided by our published research has been used by foresters, park managers, educators, natural hazards planners, researchers and others to understand the present state of our environment, and to plan for possible future changes. The distant past can be a reliable predictor of what might happen again, and is an important component of planning for the future. Over the next funding cycle we will address the following four short-term objectives. In Objective 1 we will investigate one of the most dramatic global climatic changes of the last 11,000 years, called "The Holocene Turnover" 4,200 years ago. This climate change caused megadroughts and contributed to the collapse of ancient civilizations in the Mediterranean region and elsewhere. We plan to sample, date and analyze peat deposits at high resolution on Haida Gwaii to test the hypothesis that this event also affected Western Canada, as suggested by preliminary evidence. In Objective 2 we will continue our research on the environmental history and plant biogeography of Haida Gwaii, with a focus on the last glaciation and an earlier glaciation about 57,000 years ago. The mystery of glacial refugia for plants and animals during ice age events is an area of active research. Our fossil evidence from sea-cliffs at Cape Ball indicates that some plant species survived the last two glaciations up to the present day. A second site that might confirm this pattern has been identified at sea-cliffs at Mary Point, and we propose to conduct a parallel investigation there. In Objective 3, we will extend our Eocene paleoenvironmental research using fossil plants and insects from the Okanagan Highlands of BC, one of the richest fossil areas in the world for the period of 50-53 million years ago. This "Early Eocene Climatic Optimum" followed a rapid warming event at the end of the Paleocene 56 million years ago that was followed by the hot Eocene "Greenhouse World", a period of very high biodiversity where many plants and insects diversified. In continued collaboration with Dr. S.B. Archibald, an expert on fossil insects, we plan to conduct a detailed and unbiased fossil excavation at the Quilchena, BC locality, to determine the effects of a warming climate on an ancient biotic community, for comparison with similar studies at other localities. In Objective 4, we will investigate the first mid-Paleocene plant megafossil locality BC at Kanaka Creek. It documents forest composition and climate prior to the drastically altered forest of the late Paleocene 56 million year ago due to rapid warming, that is also seen in the warm Early Eocene that follows. The fossils in my lab at SFU need to be combined with a large collection at the Geological Survey of Canada in Ottawa to further refine the climatic interpretation and plant diversity.

我的研究计划的长期目标是重建过去的环境变化及其对生态系统的影响，包括不列颠哥伦比亚省的人口。我们发表的研究提供的信息已被林业员、公园管理人员、教育工作者、自然灾害规划者、研究人员和其他人用来了解我们环境的现状，并为未来可能的变化做计划。遥远的过去可以可靠地预测可能再次发生的事情，也是规划未来的重要组成部分。在下一个筹资周期中，我们将处理以下四个短期目标。在目标1中，我们将调查过去11,000年来最戏剧性的全球气候变化之一，即4200年前的“全新世更替”。这种气候变化造成了特大旱灾，并导致地中海区域和其他地方的古代文明崩溃。我们计划对夏威夷高分辨率的泥炭沉积物进行采样、年代测定和分析，以验证初步证据表明，这一事件也影响了加拿大西部的假设。在目标2中，我们将继续研究海达岛的环境历史和植物生物地理学，重点是最后一次冰川和大约57,000年前的早期冰川。冰河时期植物和动物的冰川避难所之谜是一个活跃的研究领域。我们在鲍尔角的海崖上发现的化石证据表明，一些植物物种在过去的两次冰川中幸存了下来，直到今天。另一个可能证实这一模式的地点是在玛丽角的海崖上，我们建议在那里进行一项平行的调查。在目标3中，我们将使用公元前奥卡纳根高地的植物和昆虫化石来扩展我们的始新世古环境研究，该高地是5000-5300万年前世界上化石最丰富的地区之一。这是在5600万年前古新世末期发生的一次快速变暖事件之后的“始新世早期气候最佳时期”，紧随其后的是炎热的始新世“温室世界”，那是一个生物多样性非常高的时期，许多植物和昆虫多样化。在与昆虫化石专家S.B.阿奇博尔德博士的持续合作下，我们计划在不列颠哥伦比亚省奎尔切纳进行一次详细而公正的化石挖掘，以确定气候变暖对一个古老生物群落的影响，并与其他地区的类似研究进行比较。在目标4中，我们将调查Kanaka Creek的第一个古新世中期巨型植物地点BC。它记录了5600万年前由于快速变暖而发生剧烈变化的古新世晚期森林之前的森林组成和气候，这也出现在随后温暖的始新世早期。我在SFU的实验室里的化石需要与渥太华加拿大地质调查局的大量收藏结合起来，以进一步完善气候解释和植物多样性。