Effect of phosphorus concentration on growth rate of Chlamydomonas reinhardtii

  • Nick de Lello
  • Jagatjit Garha
  • David Infanti
  • Johathan Raj


Phosphorus is an element that exists naturally in living organisms and the environment. The levels of phosphorus in ecosystems is impacted by human activities such as run-off from agricultural fertilizers, industrial waste, and mining, to name a few. This in turn affects the organisms living in that habitat. Unicellular algae, Chlamydomonas reinhardtii, are a key part of the salmon food web and are heavily influenced by freshwater nutrient levels. In this study, the relationship between the growth of C. reinhardtii and phosphorus concentration in the growth media was evaluated. Average growth rate was calculated using the measured cell densities in different treatment groups of varying phosphorus concentration over a two week period. Using a one-way ANOVA ongrowth rates of different treatment groups, it was determined that there is a statistically significant increase in growth rate of C. reinhardtii at higher phosphorus concentrations, with the 45mg of phosphorus/L treatment having the largest growth rate.