Luquillo CZO: The role of hot spots and hot moments in tropical landscape evolution and functioning of the critical zone

临界区(CZ)的结构和功能在维持地球生命支持系统中起着核心作用。在卢基洛临界区观测站(LCZO1)的第一阶段，研究人员发现，岩石类型、深部风化、地貌和地形的差异是关键CZ过程的主要驱动因素，如养分供应、温室气体排放以及水量和水质。在此基础上，LCZO2将评估CZ中“热点和热点时刻”的作用：对整个环境产生不成比例影响的位置或时间段。“热点和热点时刻”与湿润的热带环境特别相关，如LCZO，这些环境的特点是在空间和时间上具有高度的物理、地球化学和生物多样性。临界区过程可以发生在非常小到非常大的空间尺度上。例如，基岩风化发生在毫米空间尺度上，而植被和碳循环的大规模变化发生在几公里内，如沿海拔梯度。临界区过程也可能随着时间的推移而变化；土壤中的氧化还原反应在几分钟的尺度上发生，而飓风和山体滑坡等灾难性事件在十年尺度上发生。研究人员将识别、量化和模拟“热点和热点时刻”在一系列CZ过程中的作用，并利用这些知识预测整个卢基洛山脉和其他高温和降雨的山地地区CZ过程的速率。具体的重点领域包括：1)关键点和景观位置作为风化、土壤发育和生物地球化学循环热点的重要性；2)“热点和热点时刻”在氧化还原波动和矿物风化中对碳和养分保持和损失的作用；3)“热点”对沉积物产生的作用和“热时刻”在溪流中将沉积物、碳和养分从山上输送到海洋中的作用；以及4)气候和水文模型的发展，以在时间和空间上放大“热点和热点时刻”。收集和综合的数据将改变对CZ关键过程的控制的理解，如风化、土壤发育、C和养分储存和损失、土壤和沉积物运输，并最终改变景观演变和气候变化的影响。该项目将对热带系统中的“热点和热点时刻”提供前所未有的详细程度。这项研究的结果将使我们能够准确和准确地预测环境变化对洪水、侵蚀和山体滑坡等重要环境过程的影响。由于所有关键区域都有重大环境过程的“热点和热点时刻”，在CZ背景下发展“热点和热点时刻”的概念将促进跨站点整合，开发CZ的概念模型，并为地球科学界提供一个场所，以开发和测试CZ科学的新方法。LCZO2还将为波多黎各现有的高中“校园”环境教育项目做出贡献。该项目在将新数据和研究技术融入课程方面取得了成功的记录，除了为学生提供研究机会外，还为教师提供了专业发展。不同的合作绩效指标、高级人员和合作者群体将为研究学生和博士后提供强大的榜样。我们与地方和联邦机构以及教育机构的密切合作为政策制定者和其他利益相关者提供了接触渠道，这将帮助我们将科学转化为与政策相关的发现。非正式论坛将被用来分享我们的研究成果，并强调CZ研究对环境决策者的重要性，这些问题涉及可能填满水库的土壤侵蚀、使供水和珊瑚礁退化的水质，以及抵消全球二氧化碳增加影响的碳储存。一项包容和全面的参与计划将鼓励尚未加入LCZO2的科学家参与。跨CZO建模、开放共享数据和样本以及向公众开放的网络研讨会的计划将加强CZO的整体网络，并提高CZO科学对公众和决策者的可及性。

The structure and function of the critical zone (CZ) plays a central role in sustaining Earth's life support system. During the first phase of the Luquillo Critical Zone Observatory (LCZO1), investigators identified differences in rock type, deep weathering, geomorphology, and topography as the dominant drivers of key CZ processes such as nutrient supply, greenhouse gas emissions, and water quantity and quality. Building on this foundation, LCZO2 will evaluate the role of "hot spots and hot moments" in the CZ: locations or time periods that disproportionately impact the environment as a whole. "Hot spots and hot moments" are particularly relevant to humid tropical environments such as the LCZO, which are characterized by high physical, geochemical, and biological diversity in space and time. Critical zone processes can occur at very small to very large spatial scales. For example, bedrock weathering occurs at a millimeter spatial scale, while wholesale changes in vegetation and carbon cycling occur over several kilometers such as along elevation gradients. Critical zone processes can also vary over time; oxidation-reduction reactions occur in soils on the scale of minutes, and catastrophic events such as hurricanes and landslides occur at decadal time scales. Investigators will identify, quantify, and model the role of "hot spots and hot moments" in a range of CZ processes and use that knowledge to predict the rates of CZ processes across the Luquillo Mountains and in other montane areas with high temperature and rainfall. Specific focal areas include: 1) the importance of knickpoints and landscape position as hot spots for weathering, soil development, and biogeochemical cycling; 2) the role of "hot spots and hot moments" in redox fluctuations and mineral weathering for C and nutrient retention and loss; 3) the role of "hot spots" for sediment production and "hot moments" in stream flow for the transport of sediment, C, and nutrients from mountains to the sea; and 4) the development of climate and hydrologic models to scale up "hot spots and hot moments" in time and space. The data collected and synthesized will transform the understanding of the controls on key CZ processes such as weathering, soil development, C and nutrient storage and loss, soil and sediment transport, and ultimately landscape evolution and the effects of climate change. The project will provide an unprecedented level of detail on "hot spots and hot moments" in a tropical system. The results of this research will allow us to accurately and precisely 'earthcast' the effects of environmental change on important environmental processes such as flooding, erosion, and landslides. Because all critical zones have "hot spots and hot moments" of significant environmental processes, the development of the "hot spots and hot moments" concept in the CZ context will promote cross-site integration, the development of conceptual models of the CZ, and provide a venue for the Earth science community to develop and test novel approaches to CZ science.The LCZO2 will continue to collaborate with University of Puerto Rico (UPR) students and scientists to enhance the participation of underrepresented groups in the Earth and environmental sciences. LCZO2 will also contribute to an existing 'Schoolyard' environmental education program at high schools in Puerto Rico. This program has a successful record of incorporating new data and research techniques into the curriculum and provides professional development for the teachers in addition to research opportunities for students. The diverse group of co-PIs, senior personnel, and collaborators will provide strong role models for research students and postdocs. Our robust collaborations with local and federal agencies and educational institutions provide access to policy makers and other stakeholders that will help us to translate science into policy-relevant findings. Informal forums will be used to share our research findings and to emphasize the significance of CZ research to environmental decision makers dealing with questions such as soil erosion that can fill reservoirs, water quality that degrades water supply and coral reefs, and carbon storage that counteracts the effects of global increases in carbon dioxide. An inclusive and comprehensive engagement plan will encourage participation by scientists not yet affiliated with the LCZO2. The plans for cross-CZO modeling, open sharing of data and samples, and cyberseminars that are open to the public will strengthen the CZO network as a whole and enhance the availability of CZ science to the public and decision-makers.