Biodiversity of Sulfate Reducing Bacteria in Mercury-Contaminated Beaver Ponds at Avery Brook

Abstract

Beaver ponds act as mercury sinks, exhibiting favorable conditions for the production of neurotoxic methylmercury by sulfate reducing bacteria (SRBs), a group of bacteria that are characterized by function (sulfate reduction) rather than phylogeny.  This study was conducted to explore the diversity of SRB communities inhabiting microenvironments at the sediment-water interface in one beaver pond located on the Avery Brook stream system in the Conway State Forest.  Clone libraries were constructed in order to capture some of the diversity of sulfate-reducing bacteria as well as a biogeographic pattern.  Though the clone libraries did not reveal a biogeographic pattern, the results showed an unprecedented amount of SRB diversity in all sampled microenvironments.