title: Seasonality of Chesapeake Bay bacterioplankton species.
abstract: Bacteria, gamma-subclass of Proteobacteria, Vibrio-Photobacterium, Vibrio vulnificus, Vibrio cholerae-Vibrio mimicus, and Vibrio cincinnatiensis in water samples collected from the Choptank River in Chesapeake Bay from 15 April to 16 December 1996 were enumerated using a fluorescent oligonucleotide direct-counting (FODC) procedure. FODC results obtained using a Bacteria taxon-specific probe ranged from one-third the number of to the same number as that obtained by the acridine orange direct count (AODC) procedure. The abundance of individual taxa (per liter) ranged from 0.25 x 10(10) to 2.6 x 10(10) Bacteria, 0.32 x 10(8) to 3.1 x 10(8) gamma-Proteobacteria, 0.2 x 10(8) to 2.1 x 10(8) Vibrio-Photobacterium, 0.5 x 10(7) to 10 x 10(7) V. vulnificus, 0.2 x 10(6) to 6 x 10(6) V. cholerae-V. mimicus, and 0.5 x 10(5) to 8 x 10(5) V. cincinnatiensis. The occurrence of all taxa monitored in this study was higher in summer; however, these taxa made up a larger proportion of the Bacteria when the water temperature was low. Large fluctuations in species abundance as well as in percent composition of Vibrio-Photobacterium occurred from week to week, indicating that localized blooms of these taxa occur. The cross-Choptank River transect sample profile of V. vulnificus and V. cholerae-V. mimicus varied significantly in abundance, and trans-Choptank River transect samples revealed a patchy distribution.
authors.affiliation: Center of Marine Biotechnology, University of Maryland Biotechnology Institute, Baltimore, Maryland 21202, USA.
authors.forename: J F
authors.initials: JF
authors.lastname: Heidelberg
authors.forename: K B
authors.initials: KB
authors.lastname: Heidelberg
authors.forename: R R
authors.initials: RR
authors.lastname: Colwell
mesh_terms: D000165:Acridine Orange / Q000378:metabolism; D001419:Bacteria / Q000145:classification*; D018407:Bacterial Physiological Phenomena; D004463:Ecology; D008386:Marine Biology; D008396:Maryland; D012621:Seasons; D014867:Water / Q000032:analysis; D014871:Water Microbiology
chemical_list: D014867:Water; D000165:Acridine Orange