New Insights into the Degradation Dynamics of Organic Material in the Seafloor
Published:25 Jul.2024 Source:MARUM - Center for Marine Environmental Sciences, University of Bremen
The long-term deposition of organic material in sediments on the ocean floor is a key process in the global carbon cycle. The question of whether, from a chemical perspective, the deposited material is more similar to marine algae or the microorganisms that decompose the algal biomass is largely unresolved.
For their study, the team fed organic material labeled with 13C carbon -- either an algae-lipid mix or crude proteins -- and observed it in the laboratory for 400 days. The team has found that microbial communities can be stimulated by the addition of lipids and proteins and not only decompose fresh biomass that is easier to digest, but also decompose more of the old organic carbon that is otherwise difficult to break down.
As part of this cluster's research, the study has provided crucial insights into the link between organic matter deposition events and the long-term preservation of organic carbon and thus connects the research units Receiver, Reactor and Recorder. The input of fresh organic matter into the seafloor could increase due to climate-related changes in the environment. These will not only have a direct impact on the microorganisms living on and in the ocean floor, but also on the carbon cycle and thus on the feedback with the climate system in a way that is still largely unexplored.