Paleo-archives of past cultures, seabirds, and their changing connectivity to ecosystems

过去文化、海鸟及其与生态系统不断变化的联系的古档案

• 批准号: RGPIN-2020-06045
• 负责人: Hargan, Kathryn
• 金额: $ 2.04万
• 依托单位: Memorial University of Newfoundland
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=745733
• 关键词: Paleo; archives; past; cultures; seabirds

Natural, long-term environmental fluctuations and anthropogenic impacts to coastal regions can markedly alter wildlife populations, and in turn affect the people that rely on them. Over the past ~8000 years, Newfoundland and Labrador had at least three pre-European settlement episodes by distinct cultural groups: Maritime Archaic, Paleoeskimo, and Indigenous (Beothuk). However, discontinuities across archaeological records allude to climatic changes that likely resulted in lifestyle shifts leading to settlement abandonment or the complete extirpation of cultural groups. Past climatic changes would have influenced the availability of marine and terrestrial food resources, which in turn contributed to the success and permanency of settlements. For example, seabirds were an important component of Paleoeskimo and Beothuk culture and diet. However, modern data suggests that seabird populations decline with large changes in sea surface temperatures, and thus, seabirds would have been less likely to support past culture diet during warm periods over the Holocene. Over the next five years, my objectives are to reconstruct lake and peatland ecosystem responses to human settlements across Newfoundland and Labrador over millennia, investigating how changes in climate and European arrival influenced land use by past cultures (Theme 1), and to understand how climate variability and human pressures are linked to the long-term population dynamics of nesting seabirds (Theme 2). My research will use paleo-archives to reconstruct histories of environmental relationships between past cultures, dense animal populations (e.g., caribou, seabirds), and land use, in the context of climatic forcing. Theme 1 will examine biological and geochemical proxies in paleo-archives collected adjacent to Paleoeskimo and Indigenous basecamps to understand timing of occupation, impacts, and resulting environmental changes. Working in close collaboration with some of Canada's leading ornithologists, Theme 2 uses both modern and paleoecological studies from sub-Arctic ecosystems neighbouring seabird colonies to study past population fluctuations, placing these changes within broader environmental and climatic contexts. Notably, my research has developed fecal lipid biomarkers to track past human and seabird activity in lake catchments and peatlands, as well as to pinpoint whether animal feces were a source of organic nutrients to lakes, contributing to cultural eutrophication of aquatic ecosystems. Combining these fecal lipid biomarkers with biological subfossils that track climatic change, our dated paleo-archives will provide robust reconstructions of past environmental conditions at sites of cultural and ecological importance to early peoples in Newfoundland and Labrador and Canadians. This research has significant implications on our understanding of factors driving past ecological changes, as well as ecosystem and cultural resilience to environmental and climatic stressors.

自然的、长期的环境波动和对沿海地区的人为影响可以显著改变野生动物的数量，进而影响依赖它们的人。在过去的8000年里，纽芬兰和拉布拉多至少经历了三次不同文化群体在欧洲之前的定居：海洋古人、古埃斯基莫人和土著人(Beothuk)。然而，考古记录中的不连续暗示了气候变化可能导致生活方式的转变，导致定居点被遗弃或文化群体完全灭绝。过去的气候变化会影响海洋和陆地食物资源的可获得性，而这反过来又有助于定居点的成功和永久性。例如，海鸟是古埃斯基莫和贝苏克文化和饮食的重要组成部分。然而，现代数据表明，随着海面温度的大幅变化，海鸟数量下降，因此，海鸟在全新世温暖时期不太可能支持过去的养殖食物。在接下来的五年里，我的目标是重建纽芬兰和拉布拉多地区数千年来人类住区对湖泊和泥炭地生态系统的响应，调查气候变化和欧洲人的到来如何影响过去文化对土地利用的影响(主题1)，并了解气候变异性和人类压力如何与筑巢海鸟的长期种群动态联系起来(主题2)。我的研究将使用古档案来重建在气候强迫的背景下，过去文化、密集动物种群(例如驯鹿、海鸟)和土地利用之间的环境关系的历史。主题1将研究与古埃斯基莫和土著大本营相邻收集的古档案中的生物和地球化学指标，以了解占领的时间、影响和由此产生的环境变化。主题2与加拿大一些顶尖的鸟类学家密切合作，利用邻近海鸟群落的亚北极生态系统的现代和古生态研究来研究过去的种群波动，将这些变化置于更广泛的环境和气候背景中。值得注意的是，我的研究开发了粪便脂质生物标记物，以跟踪过去人类和海鸟在湖泊集水区和泥炭地的活动，并查明动物粪便是否是湖泊有机营养物质的来源，从而促进水生生态系统的文化富营养化。将这些粪便脂肪生物标记物与追踪气候变化的生物亚化石相结合，我们过时的古档案将提供对纽芬兰、拉布拉多和加拿大早期民族具有重要文化和生态意义的遗址过去环境条件的有力重建。这项研究对我们理解推动过去生态变化的因素，以及生态系统和文化对环境和气候压力的适应能力具有重要意义。