Collaborative Research LTREB Renewal: Tropical rain forest ecosystem responses to climatic forcings

热带雨林如何应对气温和空气中二氧化碳含量的上升，对全球气候变化和生物多样性保护具有重要意义。在过去50年中，大气中二氧化碳的年度增加受到陆地热带地区碳储存量变化的强烈影响，在温暖的年份，森林排放的热带二氧化碳更多。整个热带地区的变暖速度很快，而且正在加剧，未来五年可能会带来新的记录。 尽管热带雨林具有全球重要性，但很少有实地数据来评估这些森林对气候变化的敏感性。该项目的研究将把对热带雨林生产力和动态及其与气候的关系进行的最长时间的研究再延长五年。这项研究位于古老的低地雨林在拉塞尔瓦，哥斯达黎加，在一个网络的地块设计，使测量在景观尺度。这些测量自1997年以来一直在进行，并将在今后五年里每年实地测量森林的碳储存量，以及森林如何应对气候变化。该项目以前的研究表明，气温升高和干旱胁迫产生了强烈的负面影响，而大气二氧化碳增加对森林生产力的积极影响相比之下非常小。 进一步的测量将使研究人员能够解决关于热带雨林在二氧化碳含量较高的温暖植物上的未来的重要和未回答的问题。该项目的更广泛的科学影响包括广泛的研究培训和独特的长期数据集的开发。已经有几十名本科生、研究生和博士后参加了。该项目产生了近100份同行评审的出版物和论文，并提供了激励其他相关研究所需的数据集。今后五年将继续开发项目网站，作为全球完全开放获取所有项目数据的主要工具。此外，研究人员将继续发展与教育和非政府组织的合作，以鼓励在更广泛的公众环境中使用项目数据。

How tropical rain forests respond to rising temperatures and carbon dioxide levels in the air has major implications for global climate change and biodiversity conservation. Over the last 50 years, annual increases in atmospheric carbon dioxide have been strongly affected by changes in the amount of carbon stored in the land tropics, with greater tropical carbon dioxide emitted from the forest in warmer years. Warming has been rapid across the tropics and is intensifying, and the next five year period is likely to bring new records. In spite of the global importance of tropical rain forests, there are few field data to assess the sensitivity of these forests to changing climate. The research in this project will extend for a further five years the longest running study of tropical rain forest productivity and dynamics and their relation to climate. The research is located in old-growth lowland rain forest at La Selva, Costa Rica, in a network of plots designed for making measurements at the landscape scale. The measurements are continuous since 1997 and will provide a further five years of annual field measurements of carbon storage in the forests, and of how the forests are responding to changing climate. Previous research in this project has shown strong negative effects of increased temperature and drought stress, while positive effects of increases in atmospheric carbon dioxide on forest productivity are by comparison very small. Further measurements will enable researchers to address important and unanswered questions about the future of tropical rain forests on a warmer plant with higher levels of carbon dioxide.The broader scientific impacts of this project include extensive research training and development of unique long-term datasets. Already dozens of undergraduates, graduate students and post-docs have participated. The project has produced almost 100 peer reviewed publications and theses and has provided the datasets needed to stimulate other related research. The next five years will bring continued development of the project website as a principal tool for completely open global access to all of the project data. In addition, the researchers will continue to develop collaborations with educational and non-governmental organizations to encourage use of project data in broader general public settings.