HR: 15:45h
AN: NB44C-02 INVITED     [Abstracts]
TI: Effects of Dissolved Organic Matter Source on Wetland Bacterial Metabolism
AU: * Ward, A K
EM: award@biology.as.ua.edu
AF: University of Alabama, Department of Biological Sciences, Tuscaloosa, AL 35487 United States
AB: Wetlands are rich environments for organic matter production from a variety of wetland plant types. Investigations of the Talladega Wetland Ecosystem (TWE) in the southeastern U.S. show that bacterioplankton productivity is driven by dissolved organic carbon derived from wetland plants. The TWE is formed from a small coastal plain stream that has been dammed by beaver activity and resides in a forested catchment. In this study, bacterioplankton communities sampled from the wetland were amended with leachate from two different plants common in the TWE, the soft rush, Juncus effusus, and hazel alder, Alnus serrulata, and compared to unamended controls. The bacterioplankton response was examined by measuring bacterial carbon productivity and by an array of fluorescent microscope techniques used to distinguish metabolically active and non-active cells. Both plant leachates elicited rapid and significant increases in productivity and numbers of metabolically active bacterial cells. However, the timeframe of response, the magnitude of response, and the bacterial morphotypes varied depending on the leachate source. This study suggests that wetland bacterial communities contain different sub-component populations that may generally occur in low numbers, but that can adapt and respond rapidly to different sources of organic matter native to the wetland.
DE: 1890 Wetlands
SC: North American Benthological Society [NB]
MN: 2005 Joint Assembly