For the first time in the Adriatic Sea, we have shown the flux of organic carbon through a microbial food web during different seasons and with different trophic characteristics of the environment.
Understanding the carbon cycle is important because microbial processes influence global climate and biogeochemical cycles. The marine environment is rich in diverse microorganisms that have different requirements for carbon and play a key role in its cycling. Their functions include autotrophy, heterotrophy and photoheterotrophy. Primary carbon production takes place in the illuminated layers of the sea thanks to autotrophic picoplankton (algae and cyanobacteria), while heterotrophic and photoheterotrophic bacteria recycle carbon.
Actively growing heterotrophic and photoheterotrophic bacteria (AAF) decompose organic carbon and supply nutrients to the ecosystem. Especially in oligotrophic areas such as the central Adriatic, they play a key role in the transfer of biomass and energy, as they are an important prey for protozoa. Their growth and activity depend on various physicochemical and biological factors, so their research is important for a better understanding of ecological processes in the sea.
Considering that there has been little work observing the specific growth rates of bacterial groups in the marine environment, the contribution of this research by our Laboratory of Microbiology is exceptional and the results have directly expanded the knowledge about the contribution of selected bacterial groups to the carbon cycle, with an emphasis on AAF in the Adriatic.
This work is a result of the ADRISAAF project (UIP-2019-04-8401: Ecology of aerobic anoxygenic phototrophs in the Adriatic Sea, leader Dr. Danijela Šantić) funded by the Croatian Science Foundation and the GAČR project PhotoGemm+ (No. 19-28778X, leader Dr. Michal Koblížek).
