Abstract:
Linking community structure to ecological function is a primary goal of community ecology. In microbial ecology, advances in sequencing technology have allowed widespread profiling of community structure, and putative functions. However, whether such descriptive characterization has improved our ability to predict and model microbial response dynamics remains unclear. Structure-function relationships are particularly convoluted in microbial systems due to high levels of genetic diversity, metabolic plasticity, context dependency, and widespread functional redundancy. To this end, a wide body of research has shown that past events or historical community states can affect contemporary communities. However, the ways in which legacy effects influence microbial diversity patterns and response dynamics, particularly in the face of anthropogenic disturbance regimes, remains poorly understood. Using both an observational and experimental approach, my research aims to identify the signatures of legacy effects on microbial trait distributions, and assess whether these effects constrain or augment community response trajectories. Focusing on both soil and freshwater ecosystems, my research will investigate legacy effects from agricultural management practices and lake eutrophication, two major drivers of global change. Additionally, I will explore whether trait distributions and response patterns observed in the laboratory scale up to reflect those observed in a natural ecosystem, affected by these stressors. Broadly, my research will contribute to the overall understanding of the factors driving variation in microbial community structure, and the role of past environmental states or selection regimes play in community functional stability.