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

随着地球气候因二氧化碳和甲烷等温室气体的积累而发生变化，植物物种将适应气候变化，经历地理分布的变化，或灭绝，预计热带地区的影响最为严重。光合作用速率、叶片厚度和生长速率等功能性状可用于评估植物物种应对气候变化的能力。在这次计划访问中，美国研究人员将与哥斯达黎加合作者合作，收集初步数据，并计划一个更大的项目，研究热带植物科Mexilataceae中发现的功能性状。这是一个最大的家庭开花植物的物种发现从低地森林到高海拔云雾林。该科在大小、花形态和生长速度上表现出极大的多样性。了解生长速度和其他功能性状在该科不同谱系中的分布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小组将在哥斯达黎加的火山巴尔瓦样带上收集有关黑锥虫物种功能性状的初步数据，从拉塞尔瓦生物站的大西洋海岸低地延伸到巴尔瓦火山山顶附近的2880米。取样的性状包括生活史、生长形态和株高，以及对植物对气候的反应很重要的特征，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。对于最容易到达的地点，还将测量光合速率。这一信息将为一个更大的项目提供基础，该项目将对样带进行更密集的采样。然后将这些关于功能特征的数据与其他来源的系统发育数据相结合，以阐明适应气候变化的潜力。合作者来自威尔克斯大学、马里兰州大学、威斯康星州大学、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实地工作，帮助培养下一代热带实地生物学家作为科学家和保护功能性热带森林的倡导者。推广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.