%0 journal article %@ 1618-3193 %A Roettgers, R., Colijn, F., Dibbern, M. %D 2005 %J Berichte zur Polar- und Meeresforschung %P 82-87 %T Algal Physiology and Biooptics, Cruise Report ANT XXI/3 „EIFEX“ %U %X Beyond it different techniques were used to follow the photo-physiological changes of the phytoplankton occurring after iron addition and to estimate photosynthesis and primary production. This includes photoacclimation, i.e. effects of solar irradiance, vertical mixing of the water column and water transparency. In addition we were interested in the comparison of different variable chlorophyll fluorescence techniques and in using these different techniques to estimate primary production.