Marine sediments are locations of carbon storage. Only some deposited carbon remains stored, while most is lost as CO₂ through respiration by organisms. We report experiments to investigate the organisms responsible for marine sediment respiration. Larger organisms and microbes contributed equally to respiration. The groups competed to feed on fresh carbon. Respiration of older carbon was stimulated when both groups were present, thus burrowing activities allow microbial activity to increase.

This study examines the age and composition of carbon in tropical streams. We find that dissolved organic carbon (DOC) is centuries to millennia old, while dissolved inorganic carbon (DIC) is consistently younger, indicating a decoupling between the two. DOC age varies seasonally, with rainforest streams exporting younger DOC during high flow, while agricultural streams mobilise older DOC. Our results suggest land conversion alters carbon export, potentially worsening with climate change.

This study propoes a new method of spatialization to estimate carbon fluxes in the Brazilian Amazon biome. To do so, was used a land surface model (JULES) and two vegetation properties. The results of this spatialization resulted in a carbon fluxes of -1.34 Pg C during the year of 2021 in the entire Brazilian Amazon biome being the states of Amapa and Acre main relevant regions of carbon source.