Henryk Renk and STANISŁAW
Ochocki
Sea Fisheries Institute, Kołłątaja 1, 81-332 Gdynia, Poland
Key words: primary production, assimilation number, photosynthetic light curve, southern Baltic.
Abstract.
This work presents photosynthetic light curves for
phytoplankton of the southern Baltic Sea. The seasonal variability of phytoplankton
assimilation numbers is described using the following formula: ANB
= 3.54 - 1.83 . sin(w. x+
0.79) + 0.32 . sin(2w. x +
0.88). The application of parameters of the photosynthetic light curve,
results of measurements of chlorophyll concentration, attenuation coefficient
for scalar irradiance and the dose of PAR irradiation measured directly
below the water surface to calculate primary production is presented. The
results obtained are compared with the in situ measurements of the primary
production. The correlation of results obtained from in situ
measurements and based on calculations using the photosynthetic light curve
is good. The mean assimilation numbers determined were used to calculate
the average primary production in the Gdańsk Deep and the Bornholm Deep,
which are, respectively, 133 and 102 g C . m-2
. year-1.