Luquillo LTER Program 4: Understanding Change in the Ecosystems of Northeastern Puerto Rico

Luquillo LTER 计划 4：了解波多黎各东北部生态系统的变化

• 批准号: 0620910
• 负责人: Nicholas Brokaw
• 金额: $ 492万
• 依托单位: University of Puerto Rico-Rio Piedras
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-12-01 至 2015-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0620910&HistoricalAwards=false
• 关键词: Luquillo; LTER; Program; Understanding; Change

The Luquillo Long-Term Ecological Research Program (LUQ) focuses on understanding factors driving long-term change in tropical forest ecosystems in the Luquillo Mountains of Puerto Rico. Building on an earlier emphasis on natural disturbances (hurricanes, landslides, droughts, floods) and ecosystem responses, LUQ will continue studies of ecosystem structure and processes in mid-elevation tabonuco forest, extend research into other forest types along an elevation gradient, and begin investigations of regional-scale processes affecting the Luquillo Mountains. Four approaches will be used: long-term experiments and measurements, comparative analyses among different forest communities, gradient analysis from forest to urban, and synthesis using conceptual and simulation models.Mounting evidence suggests that increasing hurricane intensity, declining rainfall in the mountains, and rising temperature in lowland urbanized areas can significantly affect the ecosystems of the Luquillo Mountains. In this context, the overarching question is: How do changes in disturbance regime and climate alter biogeochemical cycles, biotic structure, and ecosystem services? This leads to three specific questions addressing key elements of the LUQ conceptual framework:1) What controls variation in carbon and nutrient fluxes, and how are these variations modified by disturbance? Many processes in the Luquillo Mountains exhibit well defined seasonality and links to climate. Understanding these relationships is essential for determining the sensitivity of biota and biogeochemical cycling to environmental change. 2) Are changes in temperature, rainfall, light and wind (climate) along the Luquillo elevation gradient sufficient to explain variation in biogeochemical processes and biotic structure? LUQ proposes to study linear and non-linear trends in climate with elevation in the Luquillo Mountains as drivers of ecosystem processes and the distribution of organisms. By improving understanding of the importance of biotic and abiotic factors in determining the distribution of organisms over spatial gradients in tropical mountains, scientists will increase their ability to understand the effects of change.3) How important are changes in land-use in determining long-term ecosystembiogeochemistry, biotic structure, and services? Land-use and land-cover are changingdramatically in northeastern Puerto Rico in response to socioeconomic changes. LUQ proposes to examine the long-term effects of land-use and land-cover change on a range of features, including regional and local climate, tree species composition, stream ecology, and a key ecosystem service: the delivery of clean water for humans.The proposed research will provide an improved scientific framework for the management of tropical ecosystems and ecosystem services. It will do so both through conceptual advances and documentation of human disturbance and ecosystem response. The project will continue to produce a cadre of young and minority scientists who are versed in linking population and ecosystem approaches to evaluating environmental change, and will provide them with skills that can be applied in tropical regions or elsewhere. LUQ has developed a comprehensive education program involving teachers at a network of six high schools and a web-based middle school curriculum for teaching ecology. Additional outreach activities are directed at improving the general public's appreciation of the water resources provided to surrounding towns by streams draining the Luquillo Mountains.

卢基洛长期生态研究计划(LUQ)的重点是了解波多黎各卢基洛山脉热带森林生态系统长期变化的驱动因素。在早先强调自然干扰(飓风、滑坡、干旱、洪水)和生态系统反应的基础上，LUQ将继续研究中等海拔禁忌森林的生态系统结构和过程，沿着海拔梯度扩展对其他森林类型的研究，并开始调查影响卢基洛山脉的区域尺度过程。将采用四种方法：长期实验和测量，不同森林群落之间的比较分析，从森林到城市的梯度分析，以及概念和模拟模型的综合。越来越多的证据表明，飓风强度的增加，山区降雨量的减少，以及低地城市化地区气温的上升，都会对卢基洛山脉的生态系统产生重大影响。在此背景下，首要问题是：干扰机制和气候的变化如何改变生物地球化学循环、生物结构和生态系统服务？这导致了涉及LUQ概念框架的关键要素的三个具体问题：1)是什么控制了碳和营养通量的变化，以及这些变化是如何被干扰所改变的？卢基洛山脉的许多过程表现出明确的季节性和与气候的联系。了解这些关系对于确定生物群和生物地球化学循环对环境变化的敏感性至关重要。2)沿卢基洛海拔梯度的温度、降雨、光照和风(气候)的变化是否足以解释生物地球化学过程和生物结构的变化？Luq建议研究气候的线性和非线性趋势，将卢基洛山脉的海拔作为生态系统过程和生物分布的驱动因素。通过更好地理解生物和非生物因素在决定热带山区生物在空间梯度上的分布的重要性，科学家将提高他们理解变化影响的能力。3)土地利用的变化在决定长期生态系统生物地球化学、生物结构和服务方面的重要性有多大？波多黎各东北部的土地利用和土地覆盖正在发生巨大变化，以应对社会经济变化。Luq建议研究土地利用和土地覆盖变化对一系列特征的长期影响，包括区域和当地气候、树种组成、溪流生态和一项关键的生态系统服务：为人类提供清洁的水。拟议的研究将为热带生态系统和生态系统服务的管理提供更好的科学框架。它将通过概念上的进步和人类干扰和生态系统反应的记录来做到这一点。该项目将继续培养一批年轻和少数族裔的科学家，他们精通将人口和生态系统方法联系起来评估环境变化，并将向他们提供可应用于热带地区或其他地方的技能。Luq开发了一个由六所高中的教师参与的综合教育项目，并为教学生态开发了一个基于网络的中学课程。更多的外联活动旨在提高公众对流经卢基洛山脉的溪流向周围城镇提供的水资源的认识。