Potential of marine CDR for Carbon and nutrient fixation - Master Thesis 🌊

I am starting to write my Master Thesis in the above named field of research. Therefore I am really interested in your opinion about the potential of MCDR in open oceans and especially for semi-enclosed and shelf seas.

What kind of roles will the evolution of nutrient supply in marginal seas play in an ocean with excess of heat?

What would be your approach to the topic? What would you be interested in?