HR: 1330h
AN: NB33L-05    [Abstracts]
TI: Characterizing the Effect of Microhabitat on Bacterial Diversity in Sediments Along Topographic Gradients
AU: * Caspar, L
EM: laura.caspar@american.edu
AF: American University, 4400 Massachusetts Ave. NW, Washington, DC 20016
AU: Bushaw-Newton, K
EM: bushaw@american.edu
AF: American University, 4400 Massachusetts Ave. NW, Washington, DC 20016
AB: Ongoing riparian restoration including the conversion of agricultural fields back to forested areas is being conducted within the Monocacy Wildlife Management area providing the opportunity to analyze bacterial microhabitat characteristics of sediments under varying degrees of disturbance. The objective of this study is to develop greater understanding of the role of physical and chemical microhabitat differences on bacterial presence within sediments in different habitat types (i.e., upland, riparian, and in-stream) and under different degrees of disturbance. Physical and chemical microhabitat components determined were temperature, percent sediment organic matter, percent sediment moisture, concentrations of ammonia, pH, and total sediment carbon and nitrogen. Total bacterial populations of sediment were measured using 4',6-diamidino-2-phenylindole (DAPI). Polymerase chain reactions have been performed selecting for universal bacterial genes and specific nitrogen fixing, nitrifying, and denitrification genes. Bacterial diversity measurements using denaturing gradient gel electrophoresis are ongoing. Remaining chemical and physical components of microhabitat have been completed and are being analyzed. Results indicate moisture inhibits bacterial abundance while nutrient presence in sediment is associated with larger bacterial biomass. These parameters of microhabitat do not have differing effects along elevations.
DE: 1899 General or miscellaneous
DE: 9901 NABS Student Award - Basic Research
SC: North American Benthological Society [NB]
MN: 2005 Joint Assembly