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

University Of Minnesota-Twin Cities, Minneapolis MN

Investigators

Abstract

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.