Effect of solar UV radiation on photosynthetic rates of Antarctic marine phytoplankton

Conference · Tue Jan 09 04:00:00 EST 1990 · EOS, Transactions, American Geophysical Union; (United States)

OSTI ID:6657475

Holm-Hansen, O ^[1]

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1. Univ. of California-San Diego, La Jolla (United States)

Our studies on effects of solar ultraviolet (UV) radiation on rates of photosynthesis by Antarcitic marine phytoplankton were carried out on board R/V Polar Duke and at Palmer Station during Nov-Dec of 1988. In situ incubation techniques were used to estimate the effect of UV radiation on primary production in the upper portion of the euphotic zone. Samples were enclosed in either quartz vessels (which transmit nearly all UV), in pyrex vessles (50% transmission at 305 nm), or in pyrex vessels enclosed within a plexiglass filter (50% transmission at 355 nm). Within the upper m of the water column photosynthetic rates in the samples exposed only to wavelengths longer than 355 nm were double the rates of the samples in quartz vessels. The magnitude of this effect decreased rapidly with depth, and no effect of UV was noticed at 20 m. Data from temperature controlled incubators where spectral irradiance to the samples was controlled by Schott filters indicated that about 75% of the total UV effect on photosynthesis was due to UV-A radiation, and about 25% to UV-B radiation. The above studies were supported with measurements of the attenuation of UV and visible light in the water column, as well as with incident spectral irradiance measured with the UV-Spectroradiometer operated by NSF at Palmer station. Our data on photosynthetic rates will be discussed in regard to the dose-response relationship, as well as to the significance of UV radiation on the total magnitude of primary production.

• OSTI ID: 6657475
• Report Number(s): CONF-9002174--
• Conference Information: Journal Name: EOS, Transactions, American Geophysical Union; (United States) Journal Volume: 71:2
• Country of Publication: United States
• Language: English

Related Subjects

560130* -- Radiation Effects on Microorganisms
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANTARCTIC OCEAN
ANTARCTIC REGIONS
ANTARCTICA
AQUATIC ORGANISMS
BIOLOGICAL EFFECTS
CHEMICAL REACTIONS
DOSE-RESPONSE RELATIONSHIPS
ELECTROMAGNETIC RADIATION
PHOTOCHEMICAL REACTIONS
PHOTOSYNTHESIS
PHYTOPLANKTON
PLANKTON
PLANTS
POLAR REGIONS
PRODUCTIVITY
RADIATIONS
SEAS
SURFACE WATERS
SYNTHESIS
ULTRAVIOLET RADIATION