WEBSTER & TANK Woody debris is an integral part of most stream ecosystems. In many streams and rivers, the highest densities and rates of production for aquatic invertebrates are associated with wood. For many aquatic invertebrates, their food base is the microbial biofilm on the surfaces of woody debris. The factors which affect the structure and function, both biological and non-biological, of these biofilms has received little consideration. This project uses measurements of microbial growth and activity to experimentally test the roles of factors such as light levels, burial, leaf litter abundance, and wood type on biofilms in stream ecosystems. This research is important because it tests some of the possible causes and mechanisms for the high rates of production associated with woody debris. Human management activities and natural disturbances affect such variables as the amount of light reaching a stream, the types and amount of vegetation, and the rates of sediment input. How these impacts might resonate through the stream ecosystem will be focused on woody debris since this habitat is a region of high biological activity. This research looks closely at this link and possible factors influencing microbial growth rates and rates of activity at this crucial interface.
