Hydrobiologist Vesela Evtimova: Most Lakes in Antarctica Absorb CO2, Contribute to Its Reduction in Atmosphere

Data from 2022 shows that most lakes in Antarctica are absorbing CO2, but we are yet to analyse the data from the second project year until we reach the final answer, said Chief Assistant Professor Vessela Evtimova, hydrobiologist at the Institute of Biodiversity and Ecosystem Research at the Bulgarian Academy of Sciences (BAS) and participant in the 31st Bulgarian Antarctic expedition.

The two-year international project, which Evtimova leads, investigates the functioning and adaptations of freshwater ecosystems and the organisms that occur in them under extreme polar conditions, including under conditions of intense ultraviolet radiation. The study consists of several components. One of them is the CO2 measurement in lakes on Livingstone Island, which is done with the help of measuring cameras that provide information on whether the lakes are receiving or releasing carbon dioxide. The other task is studying organisms living in these lakes, while the third involves studying their survival mechanisms in such extreme conditions.

Evtimova said that the 2022 data showed most lakes in Antarctica absorb CO2, but the team is yet to analyse the data from the second project year, which will give a final answer to this question. These lakes have not yet been affected by human activity, and the only lake in which CO2 release has been measured to date is at Hannah Point. The reason for this lies in the large number of animals inhabiting the area in colonies - seals, penguins and other birds contributing to the increase in organic matter in this lake through their vital activities. This may be one of the reasons for the CO2 release from a lake, Evtimova added.

The field work consists of measurements made with two measuring cameras. With one of them the team measures whether there is an intake or CO2 emission, there is a sensor for ultraviolet radiation, which is of particular importance, because in polar and mountainous regions its levels are higher, which affects the processes in the local lakes. The data from this sensor and the research related to carbon dioxide fluxes are directly linked to UV radiation, the hydrobiologist said.

"In recent years, it has become clear that rivers and lakes are very important for the cycling of CO2 in the atmosphere", Evtimova added. We now have evidence that rivers contribute significantly to atmospheric processes. She stressed on the importance of doing similar research in Antarctica, since the number of lakes in the south of Livingstone Island is increasing, thus an awareness necessity for the processes occurring in them arises. A main question in that regard is whether they contribute to the CO2 increase in the atmosphere or, conversely, are they helping the planet by absorbing some of the CO2 from the atmosphere. "I say [they are] helping the planet, because in recent years the concentration of this gas has been increasing in the atmosphere, which has been linked mainly to human pollution", Evtimova said. "If we confirm that the lakes here in Antarctica are absorbing carbon dioxide, then we will know for sure that they are contributing to its reduction in the atmosphere," the Chief Assistant Professor concluded.

BTA's Daily News editor Konstantin Karagyozov is the only member of the media who is travelling on board the ship to Livingston Island and back, and will cover the Bulgarian expedition on site throughout the stay in Antarctica.

All media outlets can use the Bulgaria-Antarctica BTA's Log for free.