NSF Postdoctoral Fellowship in Biology FY 2021: Linking soil microbiome to pulsed trace gas emissions in rewetted drylands

该行动资助2021财年NSF生物学博士后研究奖学金，研究基因组，环境和表型之间相互作用的生命规则的综合研究。该奖学金支持将以创新方式为《生活规则》领域作出贡献的研究员的研究和培训。土壤中碳和氮流失的一个主要途径是通过气体排放到大气中，这是土壤中微生物代谢的结果；许多是臭名昭著的温室气体（如二氧化碳和一氧化二氮）和影响空气质量的气体（如挥发性有机化合物和一氧化二氮）。然而，目前还不清楚是什么调节了土壤中的气体排放：它们是土壤中生物的特定特征和活动的结果，还是生物所处环境的结果？在炎热、干燥的生态系统中，土壤排放通常较低，但大排放的“脉冲”通常发生在降雨或灌溉事件之后，此时土壤足够湿润，植物和微生物的新陈代谢可以茁壮成长。这种气体脉冲现象提供了一个独特的机会，将土壤生物学的同步变化、土壤中营养物质的运动和新陈代谢释放的气体（副）产物联系起来。该研究项目将结合实验方法，将土壤过程与农业背景下的气体排放联系起来，其结果可用于设计更健康的农业系统，并大规模影响气候和空气质量；这将有利于劳动力发展伙伴关系和参与项目的不同背景的学生。研究活动将分子和同位素工具与生物地球化学分析相结合，量化微生物和营养物质对干燥土壤再湿润的反应，并将这些反应与微量气体脉冲联系起来。两个实验将在一个农业研究系统中进行，以比较土壤调节的不同方面，这些方面已知会影响微量气体脉冲，并可能扩展到微生物与环境的相互作用：(1)增加氮添加，(2)作物基因型。培训活动包括建立基因组、分子和同位素工具和分析方面的技能，所有这些都是土壤生态学的新领域，很少结合起来解释与养分循环有关的过程；指导对跨学科问题和方法感兴趣的研究生和本科生；向公众、决策者和农业实体宣传土壤健康的重要性。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2021, Integrative Research Investigating the Rules of Life Governing Interactions Between Genomes, Environment and Phenotypes. The fellowship supports research and training of the Fellow that will contribute to the area of Rules of Life in innovative ways. A major pathway of carbon and nitrogen loss from soils is via gaseous emission to the atmosphere that occurs as a result of microbial metabolism in the soil; many are notorious greenhouse gases (e.g., carbon dioxide and nitrous oxide) and gases that affect air quality (e.g., volatile organic compounds and nitric oxide). However, it is still unclear what regulates gaseous emissions from soils: are they the result of specific traits and activities of organisms in the soil or are they the result of the environment in which the organisms are living? In hot, dry ecosystems, soil emissions are generally low, but “pulses” of large emissions usually occur after rain or irrigation events when soils are wet enough for plant and microbial metabolism to thrive. This gas pulse phenomenon provides a unique opportunity to link simultaneous changes in soil biology, movement of nutrients in the soil, and the gaseous (by)products of metabolism that are released. The research project will use a combination of experimental approaches to connect soil processes to gaseous emissions in an agricultural context, where results can be used to engineer healthier farming systems and impact climate and air quality at a large scale; this will benefit workforce development partnerships and students from diverse backgrounds participating in the project. Research activities integrate molecular and isotopic tools with biogeochemical assays to quantify microbial and nutrient responses to rewetting of dry soils and relate these responses to trace gas pulses. Two experiments will be conducted in an agricultural study system to compare different aspects of soil conditioning that are known to affect trace gas pulses and presumably extend to microbe-environment interactions: (1) incremental nitrogen addition, and (2) crop genotype. Training activities include building skillsets in genomic, molecular, and isotopic tools and analyses, all of which are new frontiers of soil ecology and have rarely been used in combination to explain processes associated with nutrient cycling; mentoring graduate and undergraduate students with interest in interdisciplinary questions and approaches; and communicating the importance of soil health to the public and to policymaking and agricultural entities.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.