US-Costa Rica Planning Visit: Evolution of Functional Traits in the Melastomataceae

随着二氧化碳和甲烷等温室气体的累积，地球气候发生变化，植物物种将适应不断变化的气候，经历地理分布的变化，或者灭绝，这种影响预计在热带地区最为严重。功能性状，如光合作用速率、叶片厚度和生长速率可以用来评估植物物种对气候变化的反应能力。在这次计划访问中，美国研究人员将与哥斯达黎加的合作者合作，收集初步数据，并计划一个更大的项目，研究热带植物家族野牡丹科的功能特征。这是开花植物的最大的科之一，从低地的森林到高海拔的云雾林都有发现。该科在大小、花形态和生长速度上表现出极大的多样性，跨越这些海拔梯度。了解生长速度和其他功能特征在该家族不同谱系中的分布情况将有助于我们了解热带植物物种如何适应气候变化。一个由生理生态学家和系统学家组成的国际团队将在哥斯达黎加的伏尔干巴瓦样带收集关于黑脉体物种功能特征的初步数据。伏尔干巴瓦样带从La Selva生物站的大西洋海岸低地延伸到伏尔干巴瓦山顶附近2880米处。抽样的性状包括生活史、生长型和株高，以及对植物对气候的反应重要的特征，如叶面积、叶面积与边材面积的比率、叶厚度、叶韧性和木材密度。对于最容易接近的地点，还将测量光合作用速率。这些信息将为一个更大项目的提案提供基础，该项目将对横断面进行更密集的采样。然后，这些关于功能特征的数据将与来自其他来源的系统发育数据结合起来，以阐明适应气候变化的潜力。合作者来自威尔克斯大学、马里兰大学、威斯康星大学、哥斯达黎加大学、哥斯达黎加国立大学、加州科学院和纽约植物园。美国和哥斯达黎加的学生将参与数据收集和热带野外工作，帮助培养下一代热带野外生物学家，成为科学家和保护热带功能性森林的倡导者。外展活动将通过博物馆和植物园合作伙伴在美国以及哥斯达黎加进行。

As the earth's climate changes in response to accumulating greenhouse gases like carbon dioxide and methane, plant species will adapt to changing climate, experience changes in geographic distribution, or become extinct, with such impacts predicted to be most severe in the tropics. Functional traits such as the rate of photosynthesis, leaf thickness, and growth rate can be used to assess the ability of plant species to respond to climate change. In this planning visit, US researchers will work with Costa Rican collaborators to collect preliminary data and plan a larger project on functional traits found in the tropical plant family, Melastomataceae. This is one of largest families of flowering plants with species found from lowland forests to high elevation cloud forest. The family exhibits extreme diversity in size, floral morphology, and growth rate across such elevational gradients. Knowledge of how growth rate and other functional traits are distributed among different lineages in this family will help us understand how tropical plant species might adapt to variation in climate.An international team of physiological ecologists and systematists will collect preliminary data on functional traits for melastome species on Costa Rica's Volcan Barva Transect, which extends from Atlantic coast lowlands at La Selva Biological Station to 2880 m near the summit of Volcan Barva. Traits to be sampled include life history, growth form, and plant height as well as characteristics important for plant response to climate such as leaf area, the ratio of leaf area to sapwood area, leaf thickness, leaf toughness, and wood density. For the most accessible sites, photosynthetic rate will also be measured. This information will provide the basis for a proposal for a larger project that will more intensively sample the transect. Such data on functional traits would then be combined with phylogenetic data from other sources to elucidate the potential for adaptation to climate change. Collaborators come from Wilkes University, the University of Maryland, the University of Wisconsin, the University of Costa Rica, the National University of Costa Rica, the California Academy of Sciences and the New York Botanical Garden. U.S. and Costa Rican students will participate in data collection and tropical field work, helping to develop of the next generation of tropical field biologists as scientists and as advocates for preserving functional tropical forests. Outreach activities will be performed in the U.S. via museum and botanical garden partners, as well as in Costa Rica.