Microbial Consortia and Disturbance in Sediment Habitats

University Of South Carolina At Columbia, Columbia SC

Investigators

Abstract

DEB-0108412 - Lovell Environmental disturbance by such factors as storms, fires and predators, is a pervasive force impacting the diversity and organization of organism communities. Because of competitive interactions, higher organism typically have their peak species diversity at intermediate disturbance levels. Microbial communities are much more dependent upon positive interactions than on competition, and are organized in mutualistic consortia. The interactions among species in these consortia facilitate vital ecological functions, such as organic matter decomposition and nutrient cycling, and are highly dependent on the physical structure of undisturbed sediments and on modifications of this structure by the organisms. Among the most dramatic modifications by the resident microbiota is biofilm formation. The biofilms stabilize consortia and provide homeostasis for the microorganisms within them. We predict that unlike higher organisms, the mutualistic nature of sediment microbial assemblages will be seriously disrupted by disturbance and will take several experimental approaches to test this theory. We seek to integrate the impacts of disturbance on sediment microbiota into the theoretical and empirical framework of disturbance effects on higher organism communities. This would serve both fields by providing much needed theoretical underpinnings to an important aspect of microbial ecology.