Workshop: Using Elevational Treelines to Predict Climate Change Effects on the Future Size and Distribution of Mountain Forests; University of Idaho, August 4-7, 2015

研讨会：利用高程林线预测气候变化对山地森林未来规模和分布的影响；

• 批准号: 1523307
• 负责人: William Smith
• 金额: $ 1.76万
• 依托单位: Wake Forest University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-07-01 至 2016-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1523307&HistoricalAwards=false
• 关键词: Workshop; Using; Elevational; Treelines; Predict

Mountains cover a major portion of the Earth's land area (approximately 24%), house approximately 20% of the world's population, provide critical ecosystem services to nearly half of the world population, and often form the boundaries between countries. Most of these mountain ecosystems are covered with tree forests that are key to important, often critical, services such as water storage and supply, commercial building and heating products, recreation and tourism, all of which dictate an important need for understanding their future sustainability under future global changes. This workshop will bring together experts from around the globe in an attempt to synthesize the mechanistic causes of observed forest boundaries. Specifically, emphasis at the meeting will be placed on ecophysiological adaptations and their linkages to genetic mechanisms. The meeting will be held at a facility that offers summer experiences to high school students interested in science but underrepresented in the fields of science, technology, engineering, and mathematics. The workshop will allow direct access by students attending summer classes at the field station. The intellectual approach of the meeting will be to generate predictive capabilities about potential future shifts in the elevational distributions of mountain forests. The upper and lower treeline boundaries define this distribution pattern, and future shifts have been projected based on current scenarios of rising atmospheric carbon dioxide and global warming. Such shifts in the boundaries and, thus, size of these forests could dramatically alter a host of ecosystem services, including snowpack accumulation and water supply to agriculture and municipalities. Moreover, future forest management policies could benefit significantly from early estimates of the anticipated changes in the future size and distribution of these mountain forests. The workshop will bring together global researchers with recognized expertise for understanding how the abiotic and biotic environment influences mechanistically the elevation of the lower and upper boundaries (treelines) of mountain forests and, thus, a method for estimating future changes in the total breadth of the zonal forest bands found on mountains across the globe. Mountain forest boundaries have been recognized previously as a bellwether of climate change impacts on global ecosystems. Yet, little consensus exists regarding the specific mechanisms driving the elevations currently observed for treelines across the globe. Conflicting ideas currently exist concerning physiological constraints, including fundamental metabolic processes such as the photosynthetic capture versus the metabolic processing of carbon, plus the abiotic/biotic factors that may be limiting either. Moreover, most of the evidence for mechanisms driving treeline elevations comes from measurements on mature trees, rather than the early establishment stages when mortality is often the highest of all life stages. More specifically forest tree reproduction at treelines has been a neglected area of focus, including the idea that new seedling establishment is a critical, bottleneck life stage. Also, workshop participants will address the idea that carbon processing (sink) instead of carbon acquisition (source) limitations should be included as a missing, yet crucial, component for understanding new seedling establishment at treeline. The ultimate objective will be the formulation of a synthesis manuscript to be submitted for publication in an internationally-refereed journal with a broad readership. Another primary objective will be to involve the interaction of as many external workshop participants as possible via the K-12 program at the workshop venue (McCall Field Station, Univ Idaho), participating graduate students and Assistant Professors, and major social media outlets.

山脉覆盖了地球陆地面积的主要部分（约24%），容纳了约20%的世界人口，为近一半的世界人口提供了重要的生态系统服务，并经常形成国家之间的边界。 大多数山区生态系统都覆盖着树木林，这些树木林对于水的储存和供应、商业建筑和供暖产品、娱乐和旅游等重要的、往往是关键的服务至关重要，所有这些都表明，迫切需要了解它们在未来全球变化下的未来可持续性。 该讲习班将汇集来自地球仪各地的专家，试图综合所观察到的森林边界的机械原因。具体而言，会议的重点将放在生态生理适应及其与遗传机制的联系上。 会议将在一个为对科学感兴趣但在科学、技术、工程和数学领域代表性不足的高中生提供暑期体验的设施中举行。 讲习班将允许在外地站上暑期班的学生直接参加。 会议的智力方法将是建立预测能力，预测未来山林海拔分布的潜在变化。 树线的上下边界确定了这种分布模式，并根据目前大气二氧化碳上升和全球变暖的情况预测了未来的变化。 这种边界的变化以及由此导致的森林规模的变化可能会极大地改变一系列生态系统服务，包括积雪堆积以及农业和城市供水。 此外，对这些山区森林的未来规模和分布的预期变化的早期估计可大大有助于未来的森林管理政策。 讲习班将汇集具有公认专门知识的全球研究人员，以了解非生物和生物环境如何从机械上影响山区森林的上下边界（树木线）的海拔，从而找到一种方法来估计今后地球仪山区地带性森林带总宽度的变化。 山地森林边界以前被认为是气候变化对全球生态系统影响的风向标。 然而，关于目前观察到的地球仪上树木高度升高的具体机制，几乎没有共识。 目前存在关于生理限制的观点，包括基本的代谢过程，如光合捕获与碳的代谢处理，加上可能限制两者的非生物/生物因素。 此外，大部分的机制驱动树线海拔的证据来自成熟树木的测量，而不是早期建立阶段的死亡率往往是最高的所有生命阶段。更具体地说，林木线上的林木繁殖一直是一个被忽视的焦点领域，包括新幼苗建立是一个关键的瓶颈生命阶段的想法。 此外，研讨会与会者将讨论的想法，碳处理（汇），而不是碳获取（源）的限制应包括作为一个缺失的，但至关重要的，了解新的幼苗建立在树线的组成部分。最终目标将是编写一份综合手稿，提交一份具有广泛读者群的国际期刊发表。另一个主要目标将涉及尽可能多的外部研讨会参与者的互动，通过K-12计划在研讨会场地（麦考尔现场站，爱达荷州大学），参与研究生和助理教授，以及主要的社交媒体。