Macroalgae play a fundamental role in aquatic ecosystems, as they provide food, shelter and habitat for hundreds of marine species, they also produce oxygen and capture carbon dioxide (CO2) from the atmosphere through photosynthesis, an important feature that can help mitigate the effects of climate change.
INACH Communications.- A field project of the National Antarctic Science Program (Procien) led by Dr. Pamela Fernández Subiabre, a researcher at the University of Los Lagos and the i~mar Center, is studying the effects of climate change on four species of Antarctic macroalgae, precisely what is related to the increase in ocean temperatures and marine acidification, which is when the pH of the ocean is reduced (becomes more acidic) as a result of the absorption of CO2.
The researcher together with her team is participating in the LIX Antarctic Scientific Expedition (ECA 59) organized by the Chilean Antarctic Institute (INACH) with the Project “Impacts of ocean acidification and warming on carbon sequestration mechanisms (CCMs) in Antarctic algae: a phenotypic and genetic approach” that mainly consists “in evaluating these effects and impacts on different species of macroalgae that inhabit the intertidal and subtidal, depending on the carbon sequestration mechanisms that these species have”, it also mentions, that these mechanisms can be different, since they can be influenced by environmental variables such as the availability of light and carbon.
He comments that this is the second season that they have traveled to Antarctica. They had already worked during the previous summer, where they collected the maximum diversity of species found in coastal areas of Fildes Bay, King George Island. “We studied around 56 different species, from different taxonomic groups (red, green, and brown), and we analyzed their carbon sequestration mechanisms,” says Pamela Fernández.
Once these first samples were collected, short physiology experiments were carried out at the facilities of the Professor Julio Escudero base of the INACH, which allowed them to identify that there were different CO2 uptake mechanisms among these species, suggesting that their responses to climate change may be specific to some species. They also sent some tissue samples to the University of Tasmania in Australia for isotope analysis and carbon and nitrogen content.
For this second season in the field, and according to the results obtained the previous year, they are looking for specific species of ecological importance with different mechanisms of carbon sequestration, in total they delimited four species belonging to the same taxonomic group, such as Desmarestiales (algae brown) and Gigartinales (red algae), but that use different sources of carbon that can be CO2 or bicarbonate (HCO3-).
“In this campaign, we will collect and transport these species to the city of Puerto Montt, where they will be incubated under different CO2 and temperature conditions to determine their physiological and molecular responses to future oceanic conditions,” he mentions about the methodology that will be carried out soon. to develop your research.
As was well mentioned at the beginning of this note, macroalgae are a key element in aquatic ecosystems, since “they are species that provide shelter, food, and habitat for different marine organisms, such as invertebrates, fish, both in the subtidal and in the intertidal. Therefore, any negative impact on them, such as: a decrease in their abundance due to ocean warming, could trigger a negative impact at the trophic level, since not only the algae would be affected but also all the fauna that may be associated with these populations”, he warns.
Now, why is it important to study these species in Antarctica? It is because “according to the projections we have of climate change, we see that there are places where these increases in temperature or acidification of the ocean can occur at a faster rate and that is what that is projected for Antarctica”, affirms the researcher from the University of Los Lagos.
This research has the support of co-investigators Catriona Hurd (University of Tasmania, Australia), Alejandro Buschmann (U. de los Lagos), Juan Diego Gaitán-Espitia (University of Hong Kong, China), Charles Amsler (University of Alabama, United States) and Erasmo Macaya (Universidad de Concepción).
The INACH is a technical body of the Ministry of Foreign Affairs with full autonomy in everything related to Antarctic matters of a scientific, technological and dissemination nature. INACH complies with the National Antarctic Policy by encouraging the development of excellent research, effectively participating in the Antarctic Treaty System and related forums, strengthening Magallanes as the gateway to the White Continent and carrying out actions to disseminate Antarctic knowledge among citizens. .
The National Antarctic Science Program (Procien), of the INACH, is made up of the projects that it finances, organizes, coordinates and executes directly or in conjunction with other agencies in the country, since the national polar scientific activity derives from different public competitive funds. , transparent and under the peer review methodology.