TITLE:     Spatial and temporal relationships of photosynthetic 
	   parameters to inorganic nutrients and pigmentation in Antarctic
	   phytoplankton

AUTHOR:    Mark A Moline, O. Schofield, B B Prezelin

MEETING:   American Society of Limnology & Oceanography (ASLO)
	   1995 Meeting

PLACE:     University of Nevada, Reno

DATE:      11-15 June 1995


ABSTRACT:  Within the Palmer Long Term Ecological Research Program
(PAL-LTER)) at Palmer Station Antarctica, a suite of environmental
(nitrate, phosphate, silicate, % light at depth, temperature, sigma-t)
and biological data (particulate carbon and nitrogen, HPLC-determined
phytoplankton pigments, 14C photosynthesis-irradiance (P-I)
parameters) were collected at a nearshore station throughout the
1991-1992 austral summer.  Stepwise parametric and randomization
regression techniques were used to generate algorithms to predict the
temporal and spatial variability in the P-I parameters.  Nutrient and
pigment concentrations were significantly correlated to each other and
to the maximum photosynthetic rate (Pmax); however the predictive
accuracy was limited.  70% of the seasonal variability in the
light-limited slope of the P-I curve (a) was attributable to the
photosynthetic pigments while photoprotective pigments accounted for
80% of the variability in Pmax.  The predictive accuracy of the
derived algorithms are tested against field data gathered over larger
spatial (500 km) and temporal (interannual) scales.  Results are used
to comment on the utility of empirical approaches for predicting
photosynthetic parameters in the Southern Ocean.