CAREER: Microbial Allocation of Assimilated Carbon: Interactions between Temperature, Substrate Quality, and Microbial Physiology Determine Efficiency of Arctic Soil Carbon Cycling

这项职业建议旨在了解在气候变暖的情况下，目前封存在北极土壤中的大量碳储量的命运。具体来说，首席研究员（PI）将研究土壤微生物对温度升高和基质有效性变化的复杂响应。这项工作将解决以下目标：(1)确定酶降解产生的溶解有机质质量如何随温度变化；(2)确定微生物分配碳给新生长、呼吸和酶生产的碳如何随温度和底物化学变化；(3)评估温度对微生物分配活性碳的影响是否影响旧土壤有机质的分解。该方法将包括实地和实验室实验。更好地了解气候变暖将如何影响北极微生物驱动的土壤碳循环，对于减少我们对全球气候-碳反馈预测的不确定性至关重要。获奖者将通过一系列旨在教授本科生关键研究技能并提供真实研究经验的活动，将研究、教学和推广结合起来，此外还将与研究生一起学习如何成为有效的导师。他将(1)担任一个正式的本科生培训项目的教师协调员，该项目名为“本科生参与生态研究技能”（SUPER），旨在培养学生参与实践研究之前的基本研究技能，并从代表性不足的群体中招募学生；(2)提供最多26名本科生在完成SUPER项目后直接参与本拟研究的机会；(3)在高级顶点课程中教授一个为期三周的模块，重点是北极土壤生态学。学生们将在当地的高山环境中收集土壤，并在实验室中进行分析。以前参加过北极研究的学生将教其他学生如何将高山环境与北极环境进行比较。

This CAREER proposal aims to understand the fate, in a warming climate, of the large stocks of carbon that are currently sequestered in Arctic soils. Specifically, the principal investigator (PI) will study the complex response of soil microorganisms to increasing temperature and changing substrate availability. The work will address the following objectives: (1) Determine how the quality of dissolved organic matter produced by enzymatic degradation changes with temperature, (2) Determine how microbial allocation of carbon to new growth, respiration, and enzyme production changes with temperature and substrate chemistry, and (3) Evaluate whether the temperature effect on microbial allocation of labile carbon affects the decomposition of old soil organic matter. The approach will involve both field-based and laboratory experiments. An improved understanding of how climate warming will affect microbially-driven soil carbon cycling in the Arctic is critical to reduce uncertainty in our predictions of global climate-carbon feedbacks. The awardee will integrate research, teaching, and outreach through a set of activities designed to teach undergraduates critical research skills and provide real research experiences, in addition to working with graduate students to learn how to be effective mentors. He will (1) Serve as a faculty coordinator for a formal undergraduate training program called Skills for Undergraduate Participation in Ecological Research (SUPER), which aims to develop basic research skills prior to student participation in hands-on research and to recruit students from underrepresented groups; (2) Provide opportunities for up to 26 undergraduates to directly participate in this proposed research after completing the SUPER program; (3) Teach a three-week module in a senior capstone course focused on Arctic soil ecology. Students would collect soils in a local alpine environment and analyze them in the laboratory. Students that had previously participated in this Arctic research would teach the other students about how the alpine environment compares to the Arctic.