Rate of bacterial mortality in aquatic environments
A method is proposed which provides a minimum estimate of the rate of bacterial mortality in growing natural populations of planktonic bacteria. This estimate is given by the rate of decrease of radioactivity from the DNA of a (/sup 3/H)thymidine-labeled natural assemblage of bacteria after all added thymidine has been exhausted from the medium. Results obtained from river water, estuarine water, and seawater show overall bacterial mortality rates in the range 0.010 to 0.030 h/sup -1/, in good agreement with the range of growth rates measured in the same environments. Use of selective filtration through Nuclepore filters (pore size, 2 ..mu..m) allowed us to determine the contribution of microzooplankton grazing to overall bacterial mortality. Grazing rates estimated by this method ranged from 0 to 0.02 h/sup -1/.
- Research Organization:
- Univ. of Brussels, Belgium
- OSTI ID:
- 6191133
- Journal Information:
- Appl. Environ. Microbiol.; (United States), Vol. 49:6
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
BACTERIA
MORTALITY
ZOOPLANKTON
GRAZING
AQUATIC ECOSYSTEMS
CARBON CYCLE
DNA
ESTUARIES
EXPERIMENTAL DATA
GROWTH
RIVERS
SEAWATER
THYMIDINE
TRACER TECHNIQUES
TRITIUM COMPOUNDS
AQUATIC ORGANISMS
AZINES
DATA
ECOSYSTEMS
HETEROCYCLIC COMPOUNDS
HYDROGEN COMPOUNDS
INFORMATION
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
MICROORGANISMS
NUCLEIC ACIDS
NUCLEOSIDES
NUCLEOTIDES
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OXYGEN COMPOUNDS
PLANKTON
PYRIMIDINES
RIBOSIDES
STREAMS
SURFACE WATERS
WATER
550701* - Microbiology- Tracer Techniques