Effects of iron on the physiology of oceanic phytoplankton from the NE subarctic Pacific Ocean ...

• Main Author: Muggli, Deborah Lynn
• Format: Text
• Language: English
• Published: University of British Columbia 2009
• Subjects: Subarctic
• Online Access: https://dx.doi.org/10.14288/1.0053332; https://doi.library.ubc.ca/10.14288/1.0053332

The physiology of 2 oceanic phytoplankton species freshly isolated from the subarctic Pacific (Station P, 145°W, 50°N) was examined, focusing on the effects of iron (Fe) on various physiological parameters. The two species, a coccolithophore Emiliania huxleyi and a large diatom Actinocyclus sp., represent different taxonomic groups and size classes of indigenous phytoplankton found at Stn P. The effect that nitrogen source (NO3" vs. NH.4+) had on the physiology and metal nutrition of both E. huxleyi and Actinocyclus sp. under Fereplete and Fe-stressed conditions was examined. In general, the diatom responded as expected based on.theoretical energy and Fe requirement predictions, with NH4"*"-grown cells exhibiting a physiological advantage over NC>3"-grown cells under Fe-stressed conditions. In contrast, E. huxleyi exhibited no physiological advantage when grown on N H 4 + compared to NO3" under Fe-stressed conditions, largely due to the decrease in cell volume of NO3"-grown cells under Fe-stress. ...