Effects of phosphorus and nitrogen on diatom diversity and abundance in Douglas Lake.

Abstract

Previous research suggests that nitrogen and phosphorus are two nutrients important to algal growth. This experiment serves to determine which nutrient, if any, is limiting to diatoms. We accomplished this by analyzing genera composition and abundance. We used clay flowerpots filled with different nutrient combinations as substrates. There were four separate treatments: phosphorus, nitrogen, a combination of the two, and a control. The pots were submerged in Douglas Lake for algal colonization. After twelve days diatoms were collected from the pots. The samples were counted, categorized into genera, and then analyzed for differences in abundance and diversity. Contrary to our hypothesis that the phosphorus enriched pots would exhibit the greatest amount of diatom diversity, the combination treatments were, in fact, more diverse.