Excess Nitrogen and Phosphorus Yield Limited Algal Growth

Abstract

 What are the effects of nutrients on algal growth? Through measuring the density in algae with different nutrients, we are able to see how different concentrations of the nutrients can effect algal growth. We hypothesize that the bottle treated with the lowest nitrogen: phosphorous ratio will reflect the highest algal growth because phosphorous is a limiting nutrient and the growth media includes both nitrogen and phosphorous. To conduct the experiment, we utilized a photobioreactor and recorded the density of the algal solution in samples with different nutrient concentrations (cells/ mL) for two weeks. In addition, we tested the concentration of phosphorous using the HAUCH spectrometer. We discovered that the control reflected the greatest increase in density. Therefore, our hypothesis was not supported because the lowest nitrogen to phosphorous ratio did not reflect the highest growth rate of the algal solutions. Our conclusion is that maintaining a balance of the two nutrients can possibly determine the highest rates of growth in algae.