Paleoecology of Western Canada: vegetation dynamics and paleoclimate during the Quaternary and Eocene.

加拿大西部的古生态学：第四纪和始新世期间的植被动态和古气候。

• 批准号: 3835-2013
• 负责人: Mathewes, Rolf
• 金额: $ 1.97万
• 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: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=633841
• 关键词: Paleoecology; Western; Canada; vegetation; dynamics

My research program aims to reconstruct patterns of change in vegetation and ecosystem structure in Western Canada, and to use this information to assess how environmental factors, in particular, climate, are responsible for those changes. Within this framework, we are focusing on several research topics. The first area of study is the glacial and biological history of Haida Gwaii (the Queen Charlotte Islands), also known as the "Canadian Galapagos." The origin of the unique fauna and flora of the Haida Gwaii is controversial, and centres on glacial history and the likely existence of glacial refuges during the last and previous glaciation. Prior to the last glacial maximum (~20,000 years ago), there was an earlier, larger glaciation that is too old to study by radiocarbon dating methods. We will use new dating techniques and employ pollen and plant fossils on Graham Island to reconstruct plant communities and climatic conditions, and to understand the effects of climate change and disturbance on plant survival and local extinction. We will also examine pollen fossils from the sediment core of a late-glacial pond adjacent to the Kilgii Gwaay archaeological site in the South Moresby area of Haida Gwaii. Using the results, we will reconstruct the environment at this particular site, which is one of the oldest (9,500 years) human occupation sites in Haida Gwaii. Pollen analysis will also test whether a sudden cooling event (Younger Dryas) occurred here, and we will use the information to understand how very rapid global climate change affected plant, animal, and human communities. Finally, we will study the connections between rapid climatic warming and biodiversity 53-50 million years ago by using well-preserved fossil insects and plants from that period (the Early Eocene) in the Okanagan highlands of south-central BC. This period had the warmest climate since extinction of dinosaurs, and marks the beginning of ecosystems that resemble modern forests in North America, Asia, and Europe. These fossils can tell us how biodiversity changed in a past rapidly warming (and possibly future?) global climate.

我的研究项目旨在重建加拿大西部植被和生态系统结构的变化模式，并利用这些信息来评估环境因素，特别是气候，如何导致这些变化。在这个框架内，我们专注于几个研究课题。研究的第一个领域是海达群岛（夏洛特女王群岛）的冰川和生物历史，也被称为“加拿大加拉帕戈斯”。“海达冰川独特的动物群和植物群的起源是有争议的，其中心是冰川历史以及在最后一次和以前的冰川期可能存在冰川避难所。在最后一次盛冰期（约20，000年前）之前，有一个更早，更大的冰川，它太古老了，无法用放射性碳测年方法进行研究。我们将使用新的测年技术，并利用格雷厄姆岛的花粉和植物化石来重建植物群落和气候条件，并了解气候变化和干扰对植物生存和当地灭绝的影响。我们还将研究来自海达·格威的南莫尔兹比岛地区的Kilminggwaay考古遗址附近的晚冰期池塘沉积物核心的花粉化石。利用这些结果，我们将重建这个特定地点的环境，这是海达·冈底斯最古老的人类居住地点之一（9,500年）。花粉分析还将测试这里是否发生过突然变冷事件（新仙女木事件），我们将利用这些信息来了解全球气候变化对植物、动物和人类社区的影响。最后，我们将研究5300 - 5000万年前快速气候变暖与生物多样性之间的联系，方法是使用公元前中南部奥肯那根高地那个时期（始新世早期）保存完好的昆虫和植物化石。这一时期是恐龙灭绝以来最温暖的气候，标志着类似于北美、亚洲和欧洲现代森林的生态系统的开始。这些化石可以告诉我们生物多样性在过去迅速变暖（可能是未来？）全球气候