Thesis Abstract – Cottrell (1981)

Cottrell, David (1981)
Nitrogen and Phosphorous as Limiting Factors for the Growth of Bernard Field Station Lake Phytoplankton Species in Continuous Culture.
Bachelor of Arts, Pomona College, Zoology.
Advisor: Larry Oglesby.

My objective is to perfect a suitable method for maintaining unicellular freshwater algae for testing of limiting nutrients in freshwater lakes…. Continuous culture was adopted…. Once a chemostat is established, one parameter can be varied while all the others are kept constant. Since nutrient limitation is suspected to limit the growth of local and many other phytoplankton populations, nitrate and phosphate concentrations will be varied in significant amounts. The increases in nutrient availability were determined by extensive literature analysis, in order to optimize laboratory time and also to avoid precipitate forming in phosphate limitation trials.