Phytoplankton extracellular release and its relation to the seasonal cycle of dissolved organic carbon in a eutrophic lake

Journal Article · Sun Jan 01 00:00:00 EST 1978 · Limnol. Oceanogr.; (United States)

DOI:https://doi.org/10.4319/lo.1978.23.1.0112· OSTI ID:5114251

Storch, T A ^[1]; Saunders, G W

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1. State University Coll., Fredonia, NY

The concentration of total dissolved organic carbon (TDOC), the daily rates of release of extracellular dissolved organic carbon (DOC) by viable phytoplankton, and the daily rates of assimilation of the phytoplankton extracellular DOC by bacteria were investigated simultaneously from April through October in Frains Lake, Michigan. The concentration of TDOC varied aperiodically. The release of DOC by phytoplankton and its utilization by bacteria fluctuated markedly, but these processes did not play a significant role in causing the seasonal variations of TDOC. Increases in the concentration of TDOC greatly exceeded the amounts accumulated from release by the phytoplankton, even when maximum rates of phytoplankton DOC release were calculated by assuming release exclusively from a large intracellular pool not at isotopic equilibrium. In addition, bacterial utilization of the phytoplankton DOC alone could not account for decreases in TDOC concentration. Therefore, there must be other major sources of dissolved organic matter than that provided by the mechanism of extracellular release by phytoplankton. The littoral flora and the decomposition of dead particulate organic materials are the most likely sources of fluctuations of TDOC in Frains Lake.

• OSTI ID: 5114251
• Journal Information: Limnol. Oceanogr.; (United States), Vol. 23:1
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
CARBON COMPOUNDS
SEASONAL VARIATIONS
BACTERIA
DECOMPOSITION
EUTROPHICATION
LAKES
MICHIGAN
NUTRIENTS
ORGANIC COMPOUNDS
PHYTOPLANKTON
AQUATIC ORGANISMS
CHEMICAL REACTIONS
GREAT LAKES REGION
MICROORGANISMS
NORTH AMERICA
PLANKTON
SURFACE WATERS
USA
VARIATIONS
550500* - Metabolism