LTREB: Evaluation of Geothermally-modified Runoff and Nutrient Cycling in a Lowland Tropical Stream

LTREB：低地热带溪流中地热改良径流和养分循环的评估

• 批准号: 9528434
• 负责人: Catherine Pringle
• 金额: $ 27.06万
• 依托单位: University of Georgia Research Foundation Inc
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-03-15 至 2001-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9528434&HistoricalAwards=false
• 关键词: LTREB; Evaluation; Geothermally; modified; Runoff

9528434 Pringle Previous research focused on the linkage between geothermally-introduced solutes and stream ecology in lowland rain forests of Costa Rica. Results indicated that phosphorus-rich streams exist 'side-by-side' with phosphorus poor streams. The source of the high phosphorus is geothermally-modified groundwater that creates a high spatial variability in stream solute chemistry. These findings represent patterns among streams draining much of the volcanic spine of Central America. This research will build on these previous findings. The current project will evaluate stream solute chemistry and incorporate important geomorphic features associated with local watershed runoff and geothermal inputs along two major stream drainages in Costa Rica. The hypothesis to be tested states that spatial and temporal patterns in solute chemistry of surface- and ground-water are related to three major geomorphic features of the volcanic landscape. Process oriented studies in one of the study drainages will allow the linkage of stream solute chemistry and transport to ecosystem- and landscape-level processes. Experiments and stream monitoring will test the hypothesis that spatial and temporal patterns in nutrient limitation of algal growth and leaf litter decomposition in surface waters are controlled by the presence or absence of geothermally-introduced phosphorus, along with physical/hydrological characteristics of the stream channel. Results from this project will comprise the only long-term data set on stream solute chemistry for primarily lowland tropical rainforest in Central America. Stream solute chemistry and process-oriented data are of fundamental importance to scientists seeking to understand and manage tropical forests and to predict the effects of regional environmental change on these threatened ecosystems.

9528434普林格尔以前的研究集中在哥斯达黎加低地热带雨林中地热引入的溶质与河流生态之间的联系。结果表明，富磷溪流与贫磷溪流“并存”。高磷的来源是地热改造的地下水，这在水系溶质化学中造成了高度的空间变异性。这些发现代表了消耗中美洲大部分火山脊线的溪流之间的模式。这项研究将建立在这些先前发现的基础上。目前的项目将评估河流溶质化学，并纳入与哥斯达黎加两个主要河流流域的当地流域径流和地热输入有关的重要地貌特征。待检验的假设指出，地表水和地下水的溶质化学的空间和时间模式与火山景观的三个主要地貌特征有关。在其中一个研究排水系统中进行的面向过程的研究将允许将溪流溶质化学和输送与生态系统和景观水平的过程联系起来。实验和河流监测将检验这一假设，即地表水域藻类生长和凋落物分解的营养限制的时空模式受地热引入的磷的存在或不存在以及河流的物理/水文特征控制。该项目的结果将包括中美洲主要是低地热带雨林的溪流溶质化学的唯一长期数据集。水系溶质化学和面向过程的数据对于寻求了解和管理热带森林并预测区域环境变化对这些受到威胁的生态系统的影响的科学家来说是至关重要的。