The Potency of Phytoplankton in the Lakes of Universitas Indonesia (UI) as the “Carbon-Eater”: A Preliminary Study in Revealing the Lake as a Possibly Another Carbon Bank

Abstract

Abstract-Phytoplankton is well-known as microorganism that can undergo photosynthesis and can only be found in aquatic ecosystems. Universitas Indonesia (UI), Depok, has six lakes: Kenanga, Agathis, Mahoni, Puspa, Ulin, and Salam Lake. Those lakes are proved to have an important role in regulating water circulation in UI and surroundings. However, study about the role of those lakes in storing carbon which is resulted from photosynthesis done by phytoplankton has not been conducted yet. We have done this study by using the light-and-dark bottle method in five kinds of depth in each lake. That method is used to obtain net productivity (NP) value then the result converted into the carbon sequestration rate (CSR). Analysis of NP in each lake is done by comparing several parameters (depth, turbidity, and biomass). Result of our study shows that NP has negative correlation with every parameter we observed and has varied significance value, i.e. NP-depth (sig: 0.001), NP-turbidity (sig: 0.001), and NP-biomass (sig: 0.05). Based on calculations, six observed lakes have total of CSR in the amount of 12,88 kg/hour. Knowing these facts could improve our knowledge to determine what kind of lake which can be potentially used as carbon bank and maintain it wisely. IndexTerms-Carbon sequestration rate, lake, phytoplankton, primary productivity.