LTREB: Dynamics of Stream Ecosystem Responses Across Gradients of Reforestation and Changing Climate in a Tropical Dry Forest

该项目的科学和教育工作重点是通过长期研究大规模气候现象对当地生态的影响和森林恢复，增进我们对热带溪流及其流域的了解。该项目在哥斯达黎加西北部的瓜纳卡斯特保护区（ACG）建立了几条中小型河流。ACG包括各种各样的栖息地，这些栖息地在生态上是独特的，也是相互联系的，包括原始干燥森林，云雾森林和雨林。干旱森林之所以重要和令人感兴趣，是因为它是一个受到全球威胁的生物群落，与一般公众认为热带环境潮湿的看法形成鲜明对比。它还包括砍伐森林的地区，现在是热带地区最大的森林恢复项目。ACG溪流流向太平洋和加勒比海，从常年到间歇，从温暖到凉爽，从大到小。这项研究将提供对热带干旱森林恢复和成熟的河流反应的深入了解，降雨的短期和长期变化（例如，干旱或气候变化），以及人类使用的短期和长期取水（已经是整个热带地区的问题）。在解决研究课题和假设时，长期的观点是必不可少的，因为它突出了随着时间的推移和环境极端的变化，有助于确定现在和未来的热带环境。这个为期五年的项目建立在斯特劳德水研究中心14年的ACG流数据库的基础上，将在ACG LTREB数据的管理和通过互联网向公众提供数据摘要方面做出重大努力。这将加强斯特劳德研究人员所研究的温带和热带地区之间的联系（包括宾夕法尼亚州的一个LTREB地点），并允许世界各地的学生和公众观察和研究ACG季节性干旱森林的条件和活动。

The scientific and educational efforts in this project focus on advancing our understanding of tropical streams and their watersheds through the long-term study of the local ecological impacts of large-scale climatic phenomena and forest restoration. This project establishes several small to intermediate size streams of the Guanacaste Conservation Area (ACG) in northwestern Costa Rica. The ACG includes a wide variety of habitats that are ecologically distinct as well as interconnected, including virgin dry forest, cloud forest and rain forest. The dry forest is of importance and interest because it is a globally threatened biome that contrasts markedly from the general public perception that tropical environments are wet. It also includes deforested areas that now represent the largest forest restoration project in the tropics. ACG streams flow to both the Pacific and Caribbean and range from perennial to intermittent, warm to cool, and large to small. The research will provide insight into stream responses to the recovery and maturation of tropical dry forests, short- and long-term variation in rainfall (e.g., droughts or climate change), and short- and long-term water withdrawals for human uses (already an issue throughout the tropics). A long-term perspective is essential in addressing the research topics and hypotheses because it highlights changes over time and the environmental extremes that help define present and future tropical environments. This five-year project builds upon the Stroud Water Research Center 14-year database for ACG streams, and a significant effort will be made in management of ACG LTREB data and making data summaries available to the public via the Internet. This will strengthen the connection between the temperate and tropical sites studied by Stroud researchers (including a LTREB site in Pennsylvania), and allow students and the public around the world to observe and study conditions and activities in the seasonal dry forests of ACG.