Photoadaptations of photosynthesis and carbon metabolism by phytoplankton from McMurdo Sound, Antarctica. I. Species-specific and community responses to reduced irradiances

Journal Article · Thu Jan 01 00:00:00 EST 1987 · Limnol. Oceanogr.; (United States)

DOI:https://doi.org/10.4319/lo.1987.32.1.0249· OSTI ID:6586536

Rivkin, R B; Voytek, M A

Irradiance-dependent rates of photosynthesis and photosynthate labeling patterns were measured for phytoplankton in McMurdo Sound, Antarctica. Species-specific and traditional whole-water techniques were used to compare the physiological responses of algae collected in a high light environment at the ice edge and from a low light environment under the annual sea ice. There were differences among species within the same sample, for the same species isolated from high and low light environments, and when species-specific responses were compared with that of the natural assemblage. For algae collected beneath the sea ice, photosynthesis generally saturated at a lower irradiance, and the light-limited region of the P vs. I relationship had a steeper slope than for the same species collected at the ice edge. Low-light-adapted algae incorporated significantly less /sup 14/C into proteins and more into low molecular weight compounds and lipids than the same species isolated from a high light environment. Under conditions where reduced rates of protein synthesis were coupled with high rates of carbon uptake, the measurement of photosynthesis may not accurately reflect the physiological condition of the phytoplankton.

• Research Organization: Univ. of Maryland, Cambridge
• OSTI ID: 6586536
• Journal Information: Limnol. Oceanogr.; (United States), Vol. 32:1
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
CARBON 14 COMPOUNDS
METABOLISM
CARBON COMPOUNDS
PHYTOPLANKTON
PHOTOSYNTHESIS
ANTARCTICA
POPULATION DYNAMICS
SODIUM CARBONATES
SPECIES DIVERSITY
ALKALI METAL COMPOUNDS
ANTARCTIC REGIONS
AQUATIC ORGANISMS
CARBONATES
CHEMICAL REACTIONS
LABELLED COMPOUNDS
OXYGEN COMPOUNDS
PHOTOCHEMICAL REACTIONS
PLANKTON
POLAR REGIONS
SODIUM COMPOUNDS
SYNTHESIS
140505* - Solar Energy Conversion- Photochemical
Photobiological
& Thermochemical Conversion- (1980-)
560140 - Radiation Effects on Plants