Collaborative Research: A longitudinal study to test for the acclimation of individual trees to 4+ decades of climate change, and the consequences for tropical rainforests

该项目旨在提高我们对亚马逊树种适应或不适应气候变化及其对物种表现和热带森林动态的影响的了解。了解热带树木对气温上升的反应能力将增加对环境变化如何影响雨林物种的了解，并将提供宝贵的信息，为预测和管理战略提供参考。在这个项目中，研究人员将比较几十年来从许多树种的同一棵树上收集的叶片样本的关键功能和形态特征。如果正在发生驯化，研究人员预计会发现树木会改变它们的叶子特征，以抵消气候变化的影响。这将是对热带树木个体的叶片功能特征进行的第一批数十年研究之一，从而填补了关于长寿树木应对气候变化的能力以及适应对森林功能和结构的影响的知识的一个重要空白。这项研究的结果将被纳入不同的环境教育和培训活动，以提高公众对热带森林生态和保护的认识。研究人员将对秘鲁东南部坦博帕塔地区四块1公顷的森林调查地块进行普查，以评估不同森林树种的适应程度。通过将普查数据与1980-1990年代收集的约15个丰富的重点树种的标本进行比较，该团队拥有一个独特的机会来量化几十年来的变化。对于这些焦点物种的每一棵活的来源树，研究人员将收集多个年轻和成熟的日光和阴叶样本，以创建新的植物标本。然后，研究人员将对每棵焦点树的新标本和历史标本进行一系列功能和形态特征的测量。为了更好地评估树木间的变异性和对性状与树木大小关系的控制，研究人员将收集额外的样本，并测量他们发现生长在Tambopata普查地块或附近的重点物种的所有其他个体树木的功能特征。最后，研究人员还将测量过去一个世纪研究区域(亚马逊西南部)所有可用植物标本收藏的相同形态特征，以评估这些特征在空间和时间上的变化。利用收集到的数据，研究人员将分析气候和功能特征之间的关系，并测试适应是否与个体和种群水平的反应有关，如直径生长、存活和群落内相对丰度的变化。这项研究的结果将被用于为K-12学生创建教材和积极的教育活动，并将成为大学层面新的教学练习的基础。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This project aims to improve our understanding of how Amazonian tree species are, or are not, acclimating to climate change, and the consequences for species performance and tropical forest dynamics. Understanding the capacity for tropical trees to respond to rising temperatures will increase knowledge of how environmental change affects rainforest species and will provide valuable information that can inform predictions and management strategies. In this project, researchers will compare key functional and morphological traits on leaf samples collected from the same individual trees of numerous tree species over multiple decades. If acclimation is occurring, researchers expect to find that trees shift their leaf traits to offset the effects of climate change. This will be one of the first multi-decadal studies of leaf functional traits measured on individual tropical trees, thus filling an important gap in knowledge about the ability of long-lived trees to respond to climate change, as well as the consequences of acclimation for forest function and structure. The results of this research will be integrated into diverse environmental education and training initiatives to increase public awareness about the ecology and conservation of tropical forests. Researchers will census four 1-ha forest inventory plots in the Tambopata region of southeastern Peru to assess the extent of acclimation of diverse forest tree species. By comparing census data with herbarium specimens of ~15 abundant focal tree species collected in the 1980-1990s, the team has a unique opportunity to quantify changes across decades. For each living source tree of these focal species, researchers will collect multiple samples of young and mature sun and shade leaves to create new herbarium specimens. Researchers will then measure a suite of functional and morphological traits on both the new and historical herbarium specimens of each focal tree. To better assess inter-tree variability and control for trait vs. tree size relationships, researchers will collect additional samples and measure functional traits on all other individual trees of the focal species that they find growing in or near the Tambopata census plots. Finally, researchers will also measure the same suite of morphological traits on all available herbarium collections of the focal species from the study region (southwest Amazon) over the past century in order to assess how these traits vary spatially and temporally. Using the collected data, researchers will analyze the relationships between climate and functional traits and test if acclimation is related to individual and population-level responses such as diameter growth, survival, and changes in relative abundance within communities. The results of this research will be used to create teaching materials and active education activities for k-12 students and will form the foundation for new teaching exercises at the university level.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.