Advancing Arctic Paleoecology: An Integrative Approach to Understanding Species Refugia and Population Dynamics in Response to Late-Quaternary Climate Change

题目：推进北极古生态学：了解物种避难和种群动态响应晚第四纪气候变化的综合方法该项目将使用一种创新的方法来研究阿拉斯加和邻近加拿大晚第四纪气候变化中与植被响应相关的冰川避难和种群动态。基于青云杉（Picea glauca）和绿桤木（Alnus viridis）两个目标物种的数据，本研究将对以下假设进行验证：(1)在复杂地形的孤立区域内，每个物种都存在多个末次冰期最大避难所，并且这些避难所的位置因物种而异；(2)一些避难种群扩展形成现代物种范围，而另一些则主要局限于末次盛冰期的位置；(3)后冰期早期，物种内和物种间的避难种群以不同的速率和方向扩散；(4)冰川难民存在于气候速度较低的地区，冰川后移民的方向和速率由气候速度的空间格局决定。研究生和本科生将接受跨学科的培训，并获得全球变化研究的广阔视野。该项目将为三名年轻研究人员的职业发展提供智力、财政资源和指导。研究成果将广泛传播给科学界、公众和土地管理者。外联活动的核心是一个讲习班，向高中教师介绍北极气候和生态变化。通过这些老师，一大群中西部的学生将接触到北极研究的兴奋。讲习班的材料将在网上向广大读者分发。该方法将整合基因组分析、涉及遥感技术的物种分布模型、气候速度图和现有的化石数据在一个层次贝叶斯建模框架中。本研究将揭示研究区域的隐冰川避难所，阐明避难种群的景观和气候背景，并为研究晚第四纪植被发育的种群动态提供新的见解。该项目有望提供与气候变化有关的物种范围变化的空间上明确的、种群层面的细节，这些细节无法通过传统的古生态分析可靠地获得。同样重要的是，该项目可以作为一个模型，展示横切方法在研究气候变化对古记录中植物种群过程的影响方面的效用。通过该项目将开发的新方法为推进北极古生态学和促进该学科的下一代研究和培训提供了机会。

TITLE: Advancing Arctic Paleoecology: An Integrative Approach to Understanding Species Refugia and Population Dynamics in Response to Late-Quaternary Climate ChangeThis project will use an innovative approach to investigate glacial refugia and population dynamics associated with vegetation responses to late-Quaternary climate change in Alaska and adjacent Canada. The research will test the following hypotheses based on data from two target species (Picea glauca and Alnus viridis): (1) Multiple Last Glacial Maximum refugia existed for each species in isolated areas nested in a complex topography, and the locations of these refugia differed between species; (2) Some of the refugial populations expanded to form modern species ranges whereas others remained largely restricted to their Last Glacial Maximum locations; (3) Within and between species, refugial populations spread at different rates and in different directions during the early postglacial period; and (4) Glacial refugia existed in areas with low climate velocity, and the directions and rates of postglacial colonization were determined by the spatial patterns of climate velocity. Graduate and undergraduate students will receive transdisciplinary training and gain a broad perspective to global change study. This project will provide intellectual focus, financial resources, and mentorship for the career development of three young investigators. Research results will be disseminated broadly to the scientific community, the public, and land managers. The centerpiece of the outreach activities is a workshop to educate high school teachers on Arctic climate and ecological changes. Through these teachers, a large group of midwestern students will be exposed to the excitement of Arctic research. Materials from the workshop will be disseminated online to a broad audience. The approach will integrate genomic analysis, species distribution modeling that involves remote-sensing techniques, climate-velocity mapping, and existing fossil data in a hierarchical Bayesian modeling framework. The proposed research will uncover cryptic glacial refugia in the study region, elucidate the landscape and climate contexts for refugial populations, and offer new insights into population dynamics in late-Quaternary vegetation development. The project promises to provide spatially explicit, population-level details of species range shifts in relation to climate change that cannot be reliably acquired using conventional paleoecological analyses. Equally important, this project may serve as a model demonstrating the utility of a crosscutting approach to investigate the impacts of climate change on plant population processes in the paleorecord. The novel approach that will be developed through this project presents an opportunity to advance Arctic paleoecology and foster next generation research and training in the discipline.