Prying Open the Black Box: Does Microbial Community Composition Regulate Respiration in Tropical Rain Forest Soil?

细菌、真菌和一系列其他微生物是驱动许多基本土壤过程的引擎。它们回收所有植物所依赖的营养物质，分解否则会积累的有机物质，并将土壤有机物质转化为二氧化碳（CO2）。因此，尽管肉眼看不见，土壤微生物可以影响一系列全球过程，包括大气成分和全球气候。虽然微生物过程的重要性是明确的，但对负责进行土壤内过程的生物体的类型或数量知之甚少。对于陆地上最多样化的生物群落--热带雨林来说，情况尤其如此。在本项目中，将采用一套技术、观察和实验来研究调节土壤微生物群落组成的因素，并确定热带雨林生态系统的季节变化与土壤微生物群落变化的关系。 更好地了解热带森林的分解和CO2通量与各种社会问题有关，因为它们在调节全球碳和养分循环、大气化学和气候方面发挥着重要作用。该提案将为两位年轻科学家的职业生涯早期以及研究生和本科生提供关键支持。它还将推进与哥斯达黎加科学家的合作，并通过与当地非政府组织和国家公园利益攸关方组织建立伙伴关系，为哥斯达黎加西南部的外联、保护和管理目标做出贡献。

Bacteria, fungi and a suite of other microorganisms are the engines that drive many essential soil processes. They recycle the nutrients that all plants depend upon, they decompose organic materials that would otherwise accumulate, and they convert soil organic matter to carbon dioxide (CO2). Thus, though invisible to the naked eye, soil microbes can influence a suite of global processes, including atmospheric composition and global climate. While the importance of microbial processes is clear, much less is known about the types or numbers of organisms that are responsible for carrying out within-soil processes. This is particularly true for tropical rain forests, the most diverse biomes on land. In this project, a suite of techniques, observations and experiments will be applied to examine the factors that regulate soil microbial community composition, and to determine how seasonal changes in tropical rain forest ecosystems are related to changes in soil microbial communities. An improved understanding of decomposition and CO2 fluxes in tropical forests is relevant to a variety of societal issues, as they play a major role in regulating global carbon and nutrient cycles, atmospheric chemistry, and climate. This proposal will provide critical support for two junior scientists early in their careers, as well as graduate and undergraduate students. It also will advance collaborations with Costa Rican scientists and contribute to outreach, conservation and management goals in southwestern Costa Rica via established partnerships with a local nongovernmental organization and a National Park stakeholder organization.