DISSERTATION RESEARCH: Elucidating stoichiometric and biogeochemical consequences of soil heterotrophic bacterial life history strategies

对微生物群落结构和生态系统功能之间关系的机制理解是将微生物生态学从基于观察的科学转变为假设驱动的科学的关键。该项目将植物和动物的生活史策略框架应用于微生物生态学，以实现对环境条件变化的土壤细菌反应的机械、假设驱动的检查。通过研究土壤细菌的单个物种并采取整体方法，该项目研究了生长速度和效率之间的权衡在各种土壤细菌生长的营养需求和生物地球化学后果中的作用。这种整体方法可以从特征和基因组分配模式中有效地定义细菌生活史策略。生活史策略允许在个体有机体和细菌群落水平上产生假设。土壤细菌负责处理和回收大部分固定在陆地环境中的碳。通过定义生活史策略，该项目加深了对环境条件变化对土壤微生物群落动态和影响其他生态系统过程的反馈的影响的理解。在这个项目中发现的结论不仅适用于生态系统生态学领域，也适用于任何理解微生物群落功能的机制基础很重要的领域，包括生物修复、合成生态学和人类健康微生物学。

Mechanistic understanding of the relationship between microbial community structure and ecosystem function is the key to moving microbial ecology from an observation-based to a hypothesis-driven science. This project adapts a life history strategy framework developed in plants and animals to microbial ecology to enable mechanistic, hypothesis-driven examination of soil bacterial response to changes in environmental conditions. By examining individual species of soil bacteria and taking a whole-organism approach, this project investigates the role of tradeoffs between growth rate and efficiency on the nutrient requirements and biogeochemical consequences of growth across a diverse range of soil bacteria. This holistic approach allows generalizations to emerge from patterns in traits and genome allocation effectively defining bacterial life history strategies. Life history strategies allow generation of hypotheses at both the individual organism and bacterial community levels.Soil bacteria are responsible for the processing and recycling of the majority of C fixed in terrestrial environments. By defining life history strategies this project deepens understanding of the effects of changes in environmental conditions on soil microbial community dynamics and feedbacks affecting other ecosystem processes. The generalizations discovered in this project promise to be applicable not only in the field of ecosystem ecology, but anywhere understanding the mechanistic basis of microbial community function is important including bioremediation, synthetic ecology, and human health microbiology.