The Professor Marian Gieysztor PTH Third Degree Prize (2019/20 edition) for her Master's thesis was awarded to mgr Joanna Piskorska, a graduate of the second-degree course in Oceanography at the Department of Oceanography and Geography, UG. Professor Marian Gieysztor Prizes are awarded by the Polish Hydrobiological Society for outstanding master's theses in hydrobiology. The…