Response of a natural Phaeocysris population to ambient fluctuations of UVB radiation caused by Antarctic ozone depletion

During the austral spring of 1990, rotation of the Antarctic polar vortex resulted in a 2-fold change in ozone concentrations (170–380 Dobson units) over regions of the marginal ice zone of the Bellingshausen Sea. The changes in ozone caused significant variations in incident and in-water UVB fluenc...

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Bibliographic Details
Published in:Journal of Plankton Research
Main Authors: Karentz, Deneb, Spero, Howard J.
Format: Text
Language:English
Published: Oxford University Press 1995
Subjects:
Online Access:http://plankt.oxfordjournals.org/cgi/content/short/17/9/1771
https://doi.org/10.1093/plankt/17.9.1771
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Summary:During the austral spring of 1990, rotation of the Antarctic polar vortex resulted in a 2-fold change in ozone concentrations (170–380 Dobson units) over regions of the marginal ice zone of the Bellingshausen Sea. The changes in ozone caused significant variations in incident and in-water UVB fluences. Phytoplankton cell densities, nutrient concentrations, DNA concentrations and stable carbon isotope ratios (δ13C) of particulate organic and dissolved inorganic carbon were monitored for a 5-week period during the ozone fluctuations. Phaeocystis was the dominant phytoplankton taxon and cell numbers were positively correlated to ozone and the δ13C of seawater ΣCO 2 and negatively correlated to nutrient concentrations. The densities of co-occumng diatoms were not related to changes in ozone, δ13C or nutrients. These observations suggest that Phaeocystis sp. responds very rapidly and adversely to increased UVB exposure, and that seawater δ13C data may be a useful tool for assessing the physiological state of high-latitude marine communities relative to increased UVB levels.