The Effects of Temperature on the Oxygen Production of Chlamydomonas reinhardtii

  • Brian Cho
  • Simran Sidhu
  • Matthew Wong
  • Michael Wong


As a keystone species in British Columbia, salmon play a large role in the ecosystem as changes in their abundance can greatly affect the numbers of other species nearby (Hilderbrand et al., 2004). Chlamydomonas reinhardtii (C. reinhardtii) are single-celled green algae that are a major food source for salmon (Norambuena et al., 2015). Due to their abundance in streams, their oxygen (O2) production contributes to the overall O2 level of streams and can indirectly affect the health of salmon (Carter, 2005). This experiment tests the effects of simulated seasonal temperatures in Vancouver stream waters on the O2 production in C. reinhardtii. Our goal is to better understand when the most ideal time for salmon to spawn is and the impacts of changing water temperatures due to climate change may have on C. reinhardtii, and consequently on salmon populations. This was conducted by incubating live cultures for 75 minutes in 7ºC, 17ºC and 27ºC waterbaths, and measuring the change in O2 in the different treatments both pre- and post-incubation. Cell counts were performed in order to determine the O2 produced per cell. Our null hypothesis was that temperature has no effect on O2 production. By conducting a One-way ANOVA we obtained a p-value of 0.08.. Since p > 0.05, the differences between the treatments were not significant. The small sample size (n=3) limited the statistical analysis and the power. Had the sample size been larger, the p-value may have been less than 0.05. Overall, our results suggest that temperature does not have a significant effect on the O2 production of C. reinhardtii.