LTREB Renewal: Emergent landscape patterns in stream ecosystem processes resulting from groundwater/surface water interactions

这项研究的重点是如何热带溪流的水化学是由地表水和地下水输入的影响，以及这些输入，反过来，如厄尔尼诺南方涛动气候变化的影响。 这是一项长期研究的延续，该研究编制了中美洲河流化学的唯一连续长期（20年）记录。在厄尔尼诺现象造成的长时间干旱之后，缓冲不良的低地溪流在长达8个月的时间里酸度会增加100倍。这些长期酸化事件似乎是正常季节性（即旱季/雨季）趋势的放大。 该项目调查了导致这些事件的机制以及这种酸化如何影响溪流的生态。中美洲的低地溪流支持多样化的水生群落，并将大量的碳从高产的陆地生态系统输送到大气和海洋。中美洲的气候预计将减少旱季降雨量。 这种气候变化可能会对新热带河流的化学成分产生重大的有害影响。 为了更好地在全球范围内了解这些研究结果，中美洲该项目的长期数据集正在与整个热带地区的其他数据集（例如，亚马逊河、刚果河、湄公河和恒河）。此外，该项目的成果将在“生命之水/维达之水”方案中传播，其中包括在当地社区开展外联活动，并建立一个可供国际访问的网页，该网页配有关于河流养护和水质/水量问题的教学工具。

This study focuses on how the water chemistry of tropical streams is influenced by surface and groundwater inputs and how these inputs are, in turn, affected by climatic variations such as the El Nino Southern Oscillation. This is a continuation of a long-term study that has compiled the only continuous long-term (20 yrs) record of stream chemistry in Central America. Following long dry periods associated with El Nino events, poorly-buffered lowland streams exhibit 100-fold increases in acidity for up to eight months. These prolonged acidification events appear to be an amplification of normal seasonal (i.e. dry season/wet season) trends. This project investigates the mechanisms causing these events and how this acidification affects the ecology of the streams.Lowland streams in Central America support diverse aquatic communities and transport large amounts of carbon from highly productive terrestrial ecosystems to the atmosphere and ocean. The climate in Central America is predicted to have decreased dry-season rainfall. This climatic shift will likely have major deleterious effects on the chemistry of neo-tropical streams. To better understand these research findings in a more global context, the long-term data set from this project in Central America is being linked to other data sets throughout the tropics (e.g., Amazon, Congo, Mekong and Ganges Rivers). In addition, the results of this project will be disseminated in the Water for Life/Agua para la Vida program, which includes outreach activities in local communities and an internationally accessible web page equipped with teaching tools on river conservation and water quality/quantity issues.