TITLE:     Variability in the quantum yields for photosynthetic
           activity in coastal Antarctic phytoplankton and the impact on 
	   bio-optical productivity models
AUTHOR:    O. Schofield, M.A. Moline, and BB Prezelin
DATE:      12-16 Feb 1996
PLACE:     1996 Ocean Sciences Meeting, San Diego, California
 Eos, Transactions, American Geophysical Union, Vol. 76, No.3, January 16, 1996
 ASLO Feb 96

ABSTRACT:  
The spatial and temporal variability in the maximum and operational 
quantum yields were determined for coastal phytoplankton within the 
Palmer LTER sampling grid for three consecutive years (1991-1994).  
Within the database there was a range of phytoplankton communities 
(diatoms, prymnesiophytes, chrysophytes) and overall biomass levels 
(0.01 to 29 mg chl a m-3); therefore it is not surprising that the 
quantum yields were highly variable.  The degree to which environmental
(light, inorganic nutrients, and temperature) and biological 
(photosynthetic and photoprotective pigmentation) parameters could 
explain the observed variability in the quantum yields was assessed 
using both parametric and randomization regression techniques.  
Previously derived theoretical models which have been used to describe 
the behavior in the quantum yield of carbon fixation for field 
populations are tested against this database to assess their accuracy 
and behavior over space and time.  Finally, discussion will be
focused on the primary modes of photoacclimation for coastal Antarctic
phytoplankton communities.