Production rate of planktonic bacteria in the north basin of Lake Biwa, Japan

Journal Article · Tue Dec 01 04:00:00 EST 1987 · Appl. Environ. Microbiol.; (United States)

OSTI ID:5245666

Nagata, T

Vertical and seasonal variations in the cell number and production rate of planktonic bacteria were investigated at a pelagic site (water depth, ca. 72 m) of the north basin of Lake Biwa during April to October, 1986. The (methyl-/sup 3/H) thymidine uptake rate into a cold tricholoroacetic acid-insoluble fraction and the frequency of dividing cells (FDCs) were measured for each sample as indices of the bacterial production rate. The seasonal data of bacterial number, thymidine uptake rate, and bacterial growth rate based on the FDCs were correlated with one another. These bacterial variables were not correlated positively with the chlorophyll a concentration. Vertically, the maxima of both bacterial number and the thymidine uptake rate were found in the euphotic zone. The direct counting of bacteria and the measurements of thymidine uptake rate combined with the size-fractionation method revealed that more than 90% of the bacterial biomass and production rate were attributed to unattached bacteria throughout the investigation period. The carbon flux estimates of bacterial production were less certain due to the variability of the conversion factor for the thymidine uptake method and that of the calibration for the FDC method, but even when the conservative range of bacterial net production rate was used (5 to 60 ..mu..g of carbon per liter per day), it can be suggested that bacterial net production in the investigated area was a significant fraction (ca. 30%) of the level of the primary production rate in the same water basin.

• Research Organization: Kyoto Univ., Shimosakamoto, Japan
• OSTI ID: 5245666
• Journal Information: Appl. Environ. Microbiol.; (United States), Journal Name: Appl. Environ. Microbiol.; (United States) Vol. 53:12; ISSN AEMID
• Country of Publication: United States
• Language: English

Related Subjects

520100* -- Environment
Aquatic-- Basic Studies-- (-1989)
54 ENVIRONMENTAL SCIENCES
AQUATIC ORGANISMS
ASIA
AZINES
COMPARATIVE EVALUATIONS
HETEROCYCLIC COMPOUNDS
ISOTOPE APPLICATIONS
JAPAN
LABELLED COMPOUNDS
MEASURING METHODS
NUCLEOSIDES
NUCLEOTIDES
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PLANKTON
PRODUCTIVITY
PYRIMIDINES
RIBOSIDES
THYMIDINE
TRACER TECHNIQUES
TRITIUM COMPOUNDS
UPTAKE