Understanding the mechanisms of microbial community assembly, stability and function

Microbial communities inhabit almost all natural environments and perform a wide range of important natural processes. For example, microbial communities decompose organic matter and drive biogeochemical nitrogen and carbon cycles. Despite the critically important functions of microbial communities in ecosystems, our understanding of how these communities assemble and function is limited. This is in part because of the enormous diversity and complexity of such microbial communities, where a pinch of soil can contain thousands of species and billions of individual cells. To help us to understand this complexity we will build mathematical models to predict the assembly and stability of microbial communities. We will then test these models using controlled lab experiments with a simplified decomposer community; and finally, we will use our models to analyse the assembly of real-world microbial decomposer communities in the natural environment. Using this approach, we will answer three questions: First, how the individual interactions microbes have with each other determine the behaviour of the overall community they form together. Second, how variation in the environment (e.g. changes in temperature) affect this community level behaviour. And finally, how the functions that a microbial community performs together - for instance in the carbon or nitrogen cycles - can be predicted from genes that the individual microbes carry. Overall, our project will deliver a predictive understanding of how and why environmental microbial communities look and function as they do in nature, and thus enable better management of these critical components of natural ecosystems.