Effects of Sodium Phosphate and Urea on Chlorophyll Content of Lake Water across Oklahoma

Abstract

In this study, we looked at the effects of different levels of sodium phosphate in a sodium phosphate (Na3PO4) to urea (CH4N2O) ratio on eutrophication of the water and chlorophyll levels within algae. We hypothesized that if we raised the levels of sodium phosphate in the ratio, there would be a higher level of chlorophyll in the algae present in the water because sodium phosphate is a limiting nutrient in the DNA production of algae. Because of this, the presence of sodium phosphate in the water is a factor affecting the productivity of the algae growth (French 2016). To test this hypothesis, we measured the chlorophyll content in our water samples under three different nutrient conditions: equal phosphate, low phosphate, and high phosphate with a constant level of urea among all samples. The urea was important to add to our water in this experiment, because it contains nitrogen, which is another limiting factor of the growth of algae and therefore the chlorophyll content of the water. We recorded the chlorophyll content as a measure of algae growth using a spectrometer at the beginning of our experiment and seven days later. After gathering our data, we concluded that our hypothesis was not supported for our Boomer Lake or Lake Lawtonka sample. Because the chlorophyll content was measured to be highest at the equal ratio of nutrients, we can assume that the growth of algae relies on the balance of nutrients and not increased levels of a lone nutrient.