Collaborative Research: How iron states impact temperature sensitivity of heterotrophic respiration in humid tropical soils

合作研究：铁态如何影响潮湿热带土壤异养呼吸的温度敏感性

• 批准号: 2241389
• 负责人: Salvatore Calabrese
• 金额: $ 36.86万
• 依托单位: Texas A&M AgriLife Research
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-05-01 至 2026-04-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2241389&HistoricalAwards=false
• 关键词: Collaborative; Research; How; iron; states

Humid tropical forests regulate the Earth’s climate, due to their capacity to absorb large amounts of atmospheric carbon dioxide and store it in vegetation and soils. These forests are also the most impacted by changes to the climate, such as global warming. An increase in temperature may cause tropical soils to release more carbon dioxide, further contributing to warming of the atmosphere. This research evaluates how an increase in temperature can affect the release of carbon dioxide from soils, specifically carbon dioxide produced by soil microorganisms through a process called heterotrophic respiration. The research advances our understanding of the fundamental processes that regulate the functioning of soil microorganisms and their production of carbon dioxide, as well as the mechanisms that affect the ability of soils to store and stabilize carbon dioxide. The work has important implications for environmental scientists, engineers, and policy makers working to assess climate change mitigation and adaptation strategies, such as reforestation and afforestation. The project supports the development of new interdisciplinary curricular material at the intersection of microbiology, hydrology, environmental science and engineering, engages middle and high school students around the impacts of climate change to tropical forests, and trains diverse students.Iron is a relatively abundant mineral in humid tropical soils. This work evaluates how the interactions between iron cycles and soil carbon modulate the temperature sensitivity of heterotrophic respiration over time. The research is guided by the hypothesis that short-term soil organic carbon decomposition through iron reduction increases the temperature sensitivity of heterotrophic respiration. In the long-term, it is hypothesized that both microbial community adaptation and physicochemical protection of organic carbon by iron minerals reduce the temperature sensitivity. The project combines experiments and process-based modeling, leveraging the Tropical Responses to Altered Climate Experiment (TRACE), a state-of-the-art field warming experiment in the Luquillo Rainforest in Puerto Rico. Comprehensive experiments with soils sampled from control and warmed plots at TRACE inform their biogeochemical response to temperature gradients and changing iron states. A process-based soil model is applied to analyze observations and mechanistically explain the response to changing temperatures. The project includes training at the undergraduate, graduate student and postdoctoral levels.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

潮湿的热带森林可以调节地球的气候，因为它们吸收了大量大气二氧化碳并将其存储在植被和土壤中。这些森林也受到气候变化的影响，例如全球变暖。温度升高可能会导致热带土壤释放更多的二氧化碳，从而进一步导致大气变暖。这项研究评估了温度的升高如何影响土壤中二氧化碳的释放，这是土壤微生物通过称为异营呼吸的过程产生的二氧化碳。这项研究促进了我们对调节土壤微生物功能及其产生二氧化碳功能的基本过程的理解，以及影响土壤储存和稳定二氧化碳能力的机制。这项工作对环境科学家，工程师和政策制定者具有重要意义，旨在评估缓解气候变化和适应策略，例如重新造林和负担能力。该项目支持在微生物学，水文学，环境科学和工程的交集中开发新的跨学科现代材料，使中学和高中生的气候变化对热带森林的影响与中学生吸引，并培训Divers Student。这项工作评估了铁循环和土壤碳之间的相互作用如何随着时间的推移调节异养呼吸的温度灵敏度。这项研究的指导下是通过假设的假设，即短期土壤有机碳分解通过还原增加了异养呼吸的温度敏感性。从长远来看，假设微生物群落的适应性和通过铁矿物对有机碳的物理保护都降低了温度敏感性。该项目结合了实验和基于过程的建模，利用了对气候实验改变的热带反应（Trace），这是波多黎各Luquillo雨林中的最先进的场变暖实验。从对照组和温暖地块中取样的土壤进行的全面实验，将其生物地球化学对温度梯度和不断变化的铁态响应。基于过程的土壤模型用于分析观察结果并机械解释对温度变化的反应。该项目包括在本科生，研究生和博士后级别的培训。该奖项反映了NSF的法定任务，并使用基金会的知识分子优点和更广泛的影响审查标准，被视为通过评估而被视为珍贵的支持。