Dimensions: Collaborative Research: the role of microbial biodiversity in controlling nitrous oxide emissions from soils

尽管地球上有大量的微生物生物多样性，但微生物物种数量，遗传多样性和生态系统功能之间的联系仍然知之甚少。土壤在维持人类健康方面发挥着重要作用。因此，了解土壤中大量细菌物种的功能尤为重要。为了对微生物物种和土壤功能之间的关系提供新的见解，该项目将重点关注减少一种名为一氧化二氮的强效温室气体。还原氧化亚氮是土壤微生物的一项重要功能。这一减排步骤决定了有多少温室气体从土壤中排放到大气中。最近发现了一组新的基因，生物体和减少一氧化二氮的途径，这为理解这一功能提供了一个机会。该项目将培训本科生和研究生，包括来自波多黎各代表性不足群体的个人。培训将包括研讨会，研究机会，并在三个机构的本科生计划的研究经验。该项目还通过既定的K to Gray计划向公众提供外联机会。最后，本研究的研究将从两个方面提供社会效益。首先，它将提供一个机械的了解控制生产的一个重要的温室气体（一氧化二氮）。第二，它将有助于了解氮的一个重要损失途径，氮是地球上唯一最具限制性的营养素。本项目将检验一氧化二氮还原酶基因中的分类和遗传多样性的数量是由于土壤中不同的基质和环境条件而导致专业化所必需的假设。最终目标是从土壤微生物的遗传和系统发育多样性来预测一氧化二氮的减少率和一氧化二氮的排放量。该提案将集中在两个研究地点-一个在伊利诺伊州和波多黎各-和测量土壤中的一氧化二氮减少类群和基因的丰度和活动。在温度、湿度和营养水平等各种环境条件下同时测量一氧化二氮的排放率，将使这一反应的生物和非生物驱动因素得以分离。将用同位素方法独立测量的一氧化二氮消耗率对多变量统计分析的预测率进行检验。这将允许评估的微生物和环境控制的一氧化二氮的命运鲁棒模型。这个奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

Despite the vast amount of microbial biodiversity on Earth, the links among the number of microbial species, their genetic diversity, and ecosystem function remain poorly understood. Soils play an important role in sustaining human health. Therefore, it is particularly important to understand the function of the large number of bacterial species in the soil. To provide new insights into the relationship between microbial species and soil function, this project will focus on the reduction of a potent greenhouse gas called nitrous oxide. The reduction of nitrous oxide is a key function of soil microbes. This reduction step determines how much of this greenhouse gas is emitted to the atmosphere from the soil. The recent discovery of a new set of genes, organisms, and pathways that reduce nitrous oxide provides an opportunity to make progress on understanding this function. This project will train undergraduate students and graduate students, including individuals from under-represented groups from Puerto Rico. The training would include workshops, research opportunities, and a Research Experience for Undergraduates program at three institutions. The project also provides outreach opportunities to the general public through established K to Gray programs. Finally, the research from this study will provide society benefits in two ways. First, it will provide a mechanistic understanding of the controls on the production of an important greenhouse gas (nitrous oxide). Second, it will help understand an important loss pathway of nitrogen, the single most limiting nutrient on Earth.This project will test the hypothesis that the amount of taxonomic and genetic diversity in the nitrous oxide reductase gene is necessary for specialization due to different substrate and environmental conditions in the soil. The ultimate goal is to predict both nitrous oxide reduction rates and nitrous oxide emissions from the genetic and phylogenetic diversity of soil microbes. The proposal will focus on two study sites- one in Illinois and one in Puerto Rico- and measure the abundances and activities of nitrous oxide-reducing taxa and genes in the soils. Simultaneous measurements of nitrous oxide emission rates in a variety of environmental conditions such as temperature, moisture, and nutrient levels, will allow the biotic and abiotic drivers of this reaction to be separated. The predicted rates of nitrous oxide consumption from a multivariate statistical analysis will be tested with independently measured rates by isotope-based methodology. This will allow assessment of the robust model of the microbial and environmental controls of the fate of nitrous oxide.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.