SS2.05 Phylogenetic and Physiologic Successions in Aquatic Bacterial Communities
Date: Monday, June 10, 2002
Time: 2:15:00 PM
Location: Carson C
YannarellAC, University of Wisconsin-Madison, Madison, USA,
Kent, A, D, University of Wisconsin-Madison, Madison, USA, 
Lauster, G, H, University of Wisconsin-Madison, Madison, USA, 
Triplett, E, , University of Wisconsin-Madison, Madison, USA, 
Intra-annual variation in bacterioplankton community composition and its relationship to changing environmental conditions
This study examines changes in epilimnetic bacterial community composition (BCC) and addresses questions about how patterns of changing community structure reflect variation in the underlying environmental template. Bacteria were collected biweekly from an oligotrophic, a eutrophic, and a humic lake throughout the ice-free season of the year 2000, and the community structure was assessed via automated ribosomal intergenic spacer analysis (ARISA) and terminal restriction fragment length polymorphism (T-RFLP). Nonmetric multidimensional scaling (NMS) plots revealed that BCC variability between lakes was greater than variability within any given lake over the course of the year. Each lake showed periods of both extreme variability and prolonged stability in BCC at different times of the year. Comparisons with environmental variables revealed that changes in water temperature, nitrogen, and DOC were related to major changes in BCC, but simplified models based on reduced sets of environmental parameters failed to capture much of the short-term variation in BCC. The implications of these findings for small-scale studies of bacterial community composition are discussed.