Rana El-Sabaawi | MSc
How Light and Iron affect photosynthesis in the oceanic diatom,
Aquatic photosynthesis accounts for almost half of global carbon fixation. Photosynthesis by marine phytoplankton is responsible for the majority of total primary production in the ocean. In iron-limited HNLC regions, large diatoms (40-100 um) bloom when iron is added, either artificially or naturally through dust input. Small seeding populations of these large diatoms survive iron limitation in times of low iron input. I am mainly interested in the adaptation and responses of these diatoms to iron limitation. In addition, very little is known about the thermal- and photoacclimation processes in marine diatoms in general, specifically ones isolated from regions of low light and temperature conditions (i.e., psychrophilic organisms).
My thesis objectives are:
1) To develop a non-invasive technique to infer photosynthetic efficiency in marine phytoplankton using Pulse Amplitute Modulated Fluorometers.
2) To decipher the effects of iron and light limitation on the photosynthetic efficiency and physiology of Pseudo-Nitzschia sp. isolated from the Northeast Sub-Arctic Pacific (Station P).
3) To investigate the effects of light and temperature on the photosynthetic efficiency of photosystem 2 in Pseudo-Nitzschia sp.