Microbial communities are ubiquitous in our world and play important roles in biogeochemical and ecosystems processes on Earth. The ability of these microbial communities to provide these different processes is frequently tied to their community structure, which can be thought of both in terms of membership (i.e. who is there) and the relative abundance of these members. Changes in environmental conditions often lead to changes in microbial community structure as well. Microbial communities are formed through the process of assembly, which in turn is driven by the four processes of 1) Selection 2) Dispersal 3) Drift and 4) Diversification. Understanding the relative importance of each of these processes in different systems is important for predicting how microbial communities will change in response to disturbances. This dissertation presents work that uses the coal fire in Centralia, PA as a model press disturbance for understanding soil microbial community responses to and recovery from disturbance. The experiments herein aim to shed light the relative roles of Selection, Dispersal, and Drift in governing these responses in soil microbial communities experience a temperature disturbance. An observation study of a chronosequence of fire disturbance in Centralia, PA is used to generate hypotheses as to the relative roles of Selection, Dispersal, and Drift in the assembly of soil microbial communities experiencing a temperature disturbance. Further, an in depth look at some of these communities using shotgun metagenomics is used to observe specific microbial traits and characteristics selected for by the temperature disturbance. Finally, a laboratory soil mesocosm warming experiment investigates the relative influence of Dispersal and dormancy in governing responses to and recovery from disturbance.
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