Late pleistocene and holocene paleoecology and biogeography of high elevation flora and glaciation of western Canada

晚更新世和全新世古生态学以及加拿大西部高海拔植物区系和冰川作用的生物地理学

• 批准号: 90581-2006
• 负责人: Hebda, Richard
• 金额: $ 1.73万
• 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: 2007
• 资助国家: 加拿大
• 起止时间: 2007-01-01 至 2008-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=361529
• 关键词: Late; pleistocene; holocene; paleoecology; biogeography

British Columbia's (BC) rich flora and diverse ecosytems are ascribed to contemporary landscape and climate diversity. This study investigates the possibility that the biotic richness of high-elevation plants originates in part from an incomplete Cordilleran ice sheet at the end of the Pleistocene Epoch. It also examines the character and rates of change in species distributions and high elevation ecosystems during rapid climatic changes, especially warming, from glacial to non-glacial times about 10,000 years ago. Lake and wetland sediment cores and geological exposures will be dated and studied by pollen, macrofossil and charcoal analyses to reconstruct environmental history on Vancouver Island and in north central BC. Vancouver Island has geological evidence that portions of it escaped the last glaciation. North-central BC has strong evidence from the chloroplast DNA of alpine plants for a long ice-free interval. DNA studies will be carried out on alpine species to complement paleoecological studies and link modern plant distributions with glacial history. The results will shed light on the extent and timing of the last ice sheet in western Canada, provide insight into the response of high altitude species to climate warming, and perhaps explain why diverse chloroplast DNA types occur in some BC alpine plant species.

不列颠哥伦比亚省的丰富的植物群和多样的生态系统归因于当代景观和气候的多样性。本研究调查的可能性，高海拔植物的生物丰富性起源于部分从一个不完整的科迪勒拉冰盖在更新世末期。它还研究了大约10，000年前从冰期到非冰期的快速气候变化，特别是变暖期间物种分布和高海拔生态系统的特征和变化率。湖泊和湿地沉积物岩心和地质暴露将通过花粉、宏体化石和木炭分析来确定年代和研究，以重建温哥华岛和不列颠哥伦比亚省中北部的环境历史。温哥华岛有地质证据表明，它的一部分逃脱了最后一次冰川。公元前中北部有来自高山植物叶绿体DNA的强有力的证据，证明有很长的无冰期。将对高山物种进行DNA研究，以补充古生态学研究，并将现代植物分布与冰川历史联系起来。研究结果将揭示加拿大西部最后一个冰盖的范围和时间，深入了解高海拔物种对气候变暖的反应，并可能解释为什么不同的叶绿体DNA类型发生在一些BC高山植物物种中。