Collaborative Research: BoCP-Implementation: Alpine plants as a model system for biodiversity dynamics in a warming world: Integrating genetic, functional, and community approaches

美国东北部的山顶支撑着北极和高山植物的独特生态系统，这些植物在树线上方以小而孤立的斑块存在。据认为，这些植物群落自大约13，000年前冰川消退以来一直存在，经历了过去的自然气候变化以及上个世纪人为造成的变暖。这些脆弱的生态系统在文化上具有重要意义，每年吸引成千上万的徒步旅行者前往这些山峰。它们还对负责保护它们免受气候变化、践踏、过度使用和其他威胁的管理机构构成了挑战。与此同时，它们可能提供了一些线索，说明孤立的小种群如何在气候变化时期生存下来。答案是否在于植物本身，在于它们快速适应变化环境的能力？或者是他们成功的秘密在庇护的角落和基岩的缝隙，这提供了一个凉爽的避难所在炎热的？随着时间的推移，这些山顶“岛屿”上的植物在多大程度上消失了，也许又重新出现了？为了回答这些问题，来自佛蒙特大学和缅因州大学的一组研究人员将对阿迪朗达克山脉的高山湖泊、佛蒙特州的绿色山脉、新罕布什尔州的白色山脉和缅因州的卡塔赫丁进行采样，分析古代植物的DNA，以了解物种是否真的在上一个冰河时代结束后的数千年里持续存在。与此同时，他们将调查东北部高山地区的现代植物，包括野外和实验花园。最后，研究人员将在一个播客中分享他们的研究结果，展示高山植物和与它们一起工作的人，以及一个新的人工智能应用程序（在东北高山管理聚会的培训研讨会上展示），这将帮助管理人员和其他人做出明智的决定，如何最好地管理这一重要的自然遗产通过未来世纪。这项工作的总体目标是帮助科学家、志愿者和管理人员了解如何更好地支持不仅是东北部的高山植物，而且是世界上其他地区的珍稀或孤立物种面临气候变化和其他威胁的高山植物。该项目将整合古生态学、群落生态学、性状生态学、种群基因组学、和地理，以了解东北部的高山植物群落是如何聚集和持续存在的。研究小组将重点关注阿迪朗达克山脉（纽约州）、绿色山脉（VT）和白色山脉（NH）以及卡塔赫丁山脉（ME），他们将首先利用来自高山沉积物岩心的古代DNA，在物种水平上描述过去13,000年的植被动态。为了描述对历史变暖的反应变化，他们将进行植物调查，通过比较现代植物群与历史调查记录来估计上世纪的物种更替。然后，该团队将结合联合收割机的数据，从共同的花园实验，小气候传感器阵列，功能性状分析，并从人口基因组数据的结合建模，以揭示过去和当代的人口动态，并澄清microrefugia，表型可塑性和当地适应的相对作用，在推动生物多样性周转千年，百年和十年的时间尺度。这项研究将集中在六个重点类群，代表关键的高山植物功能类型（禾本科，杂类草，矮灌木）。由此产生的多维生物多样性数据将为预测模型提供信息，这些模型将在对照过去已知的生物多样性动态进行测试后与区域管理人员共享。通过这种新颖的综合方法，该项目旨在通过量化气候避难所，集合种群过程，表型可塑性，该提案由“变化中的地球上的生物多样性”计划和“刺激竞争研究的既定计划”（EPSCoR）联合资助。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The mountaintops of the northeastern United States support unique ecosystems of Arctic and alpine plants, which exist as small, isolated patches above the treeline. It is thought that these plant communities have existed since the retreat of the glaciers approximately 13,000 years ago, surviving through the natural climate changes of the past as well as human-caused warming over the last century. These vulnerable ecosystems are culturally important, drawing thousands of hikers to these peaks every year. They also pose a challenge for the management agencies tasked with protecting them from climate change, trampling, overuse, and other threats. At the same time, they may hold clues about how small, isolated populations can survive periods of climate change. Does the answer lie in the plants themselves, in their ability to adapt quickly to changing environments? Or is the secret to their success in the sheltered nooks and crannies of bedrock, which provide a cool refuge during the heat? And to what extent are plants disappearing, and perhaps reappearing, on these mountaintop “islands” over time? To answer these questions, a team of researchers from the University of Vermont and the University of Maine will sample alpine lakes in the Adirondacks, the Green Mountains of Vermont, the White Mountains of New Hampshire, and Katahdin in Maine, analyzing the DNA of ancient plants to understand whether species have truly persisted in the thousands of years since the end of the last ice age. At the same time, they’ll be investigating the modern-day plants of the northeast alpine region, both in the field and in experimental gardens. Finally, researchers will share their results in a podcast showcasing alpine plants and the people who work with them, as well as in a new AI-powered app (presented during training workshops at the Northeast Alpine Stewardship Gatherings) that will help managers and others make informed decisions about how best to steward this vital natural heritage through the coming century. The overall goal of this work is to help scientists, volunteers, and managers understand how better to support not only alpine plants across the northeast, but in other parts of the world where rare or isolated species are faced with climate change and other threats.This project will integrate tools from paleoecology, community ecology, trait ecology, population genomics, and geography to develop an understanding of how alpine plant communities in the northeast assembled and persisted. Focusing on the Adirondacks (NY), the Green (VT) and White (NH) Mountains, and Katahdin (ME), the research team will first characterize the last ~13,000 years of vegetation dynamics at the species level using ancient DNA from alpine sediment cores. To characterize changes in response to historic warming, they will then conduct plant surveys to estimate species turnover over the last century by comparing modern-day flora with historic survey records. The team will then combine data from common garden experiments, microclimate sensor arrays, functional trait analyses, and coalescent modeling from population genomic data to reveal past and contemporary demographic dynamics and clarify the relative roles of microrefugia, phenotypic plasticity, and local adaptation in driving biodiversity turnover across millennial, centennial, and decadal timescales. The study will focus on six focal taxa that represent key alpine plant functional types (graminoids, forbs, and dwarf shrubs). The resulting multi-dimensional biodiversity data will inform predictive models that will be shared with regional managers after being tested against past known biodiversity dynamics. Through this novel, integrative approach, the project aims to increase predictive power in forecasting biodiversity dynamics in fragmented populations in a warming world by quantifying the relative roles of climate refugia, metapopulation processes, phenotypic plasticity, and adaptive capacity in an integrative framework.This proposal is jointly funded by the Biodiversity on a Changing Planet program and the Established Program to Stimulate Competitive Research (EPSCoR).This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.