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.

Coccolithophores are important marine CaCO₃ producers and their biominerals, the coccoliths, partly dissolve in the upper water column where dissolution is unexpected. Studying coccolith dissolution in field samples is hampered by a paucity of experimental studies describing dissolution morphologies. Here we fill this gap by experimentally dissolving different coccolithophores and applying our results to field samples.

We present lipid-based environmental and temperature reconstructions spanning the Holocene from three European varved lakes. At each site archaea are impacted by methane which influence lake water temperature reconstructions, and bacteria appear to respond to oxygen conditions and specific lake and environmental processes. Nonetheless, bacterial temperature reconstructions are comparable to regional climate data, showing the potential of varve archives for high resolution reconstructions.

To understand human impact on climate and biodiversity, we studied fossil teeth of Gomphotherium from Miocene Portugal. Chemical patterns, like those in modern elephants, show seasonal diet changes and geophagy during dry periods. This suggests dry seasons shaped animal behavior and ecosystems, offering insights into how land life responded to past warming—and how it might react to future climate change.

We analyzed 22 years of satellite and modeled data to study how light and mixing shape phytoplankton blooms on the Argentine Continental Shelf. Blooms start earlier on the central shelf and coast, and later on the deeper, colder Patagonian Shelf. Bloom intensity is highest in nutrient-rich, well-lit waters. Light penetration and mixing are key drivers, but local ocean features also influence bloom patterns. These findings improve our ability to predict ocean productivity and ecosystem behavior.

Adjusting Rock-Eval® cycle is needed to avoid the need for post-hoc corrections to estimate soil organic (SOC) and inorganic (SIC) carbon. PYRO520 is a cycle with a pyrolysis ending at 520°C instead of 650°C to avoid SIC decomposition while preserving the SOC characterization during pyrolysis. This cycle corrects the misallocation of the end-of-pyrolysis signals and thus repeatably and accurately estimates SOC and SIC contents without using corrections, while preserving the SOC characterization.

CO₂ taken up by marine algae can escape ocean surface waters through subsequent particle formation and sinking. Representing this biological carbon pump (BCP) in Earth system models remains challenging and poses uncertainties for future projections. We show that an advanced BCP representation regionally buffers ocean biogeochemistry compared to a classical approach while both respond globally similar to climate warming. Particle microstructure turns out as a key uncertainty for sinking fluxes.

Coastal ecosystems strongly influence the global carbon cycle but remain poorly quantified. We measured surface pCO₂, CH₄, and N₂O concentrations in southwest Finland across an estuarine ecosystem. Greenhouse gases concentrations varied with salinity and habitat type. Riverine inputs and mixing with seawater, and primary production shaped greenhouse gases dynamics, emphasizing benthic control as a key yet uncertain driver of coastal carbon fluxes.

Digital hemispherical photography(DHP) is a valuable tool for monitoring leaf area index(LAI), a key factor in ecosystem productivity and climate interactions. We compared DHP with litter traps in a temperate forest and found that at a view zenith angle around 20°, both methods aligned best. We applied a calibration model to assess site variability which significantly improved accuracy. Our findings enhance the reliability of ground-based LAI monitoring, supporting better ecosystem assessments.

The present study explores the influence of biological activity in the photochemistry of the sea-surface microlayer (SML) and its implications for the emission of volatile organic compounds (VOCs) to the marine atmosphere. Experimental evidence of enhanced photochemical activity of carbonyl compounds in the SML is provided, particularly in periods of higher biological productivity, thereby offering new insights to integrate biological processes and photochemistry in the air-sea boundary.

Nitrous oxide (N₂O), a potent greenhouse gas, is released from coastal seas & estuaries, yet we don't fully understand how it is formed and consumed. In this study we collected water from several sites in the central Baltic Sea. N₂O came from ammonia in oxic waters. Deep waters with low to no oxygen noted more active N₂O cycling. The seafloor was a source in some areas. Typically N₂O is produced by bacteria, but our results indicate possibility of other players like fungi or chemical reactions.

Due to climate change shifts in ecosystem structure and function have been increasingly documented in marine ecosystems around the globe. We tested whether a marine biogeochemical model can predict shifts to alternative regimes in plankton and biogeochemical processes under environmental perturbations. Simulations show that perturbations can drive the system into new regimes, with responses that are either reversible or hysteretic, depending on the type and intensity of the disturbance.

Nannoconus, a major marine planktonic biocarbonate producer of the Early Cretaceous (150–120 Ma), biomineralized heavy (200–1400 picogram) skeletons (5–20 μm) of interlocking lamellae spanned around a central canal, by an unknown process. With the first-ever application of synchrotron-based ptychographic X-ray computed tomography (PXCT) of nanometric resolution, we reconstructed the 3D skeleton by combining segments of lamellae and inferred its possible biomolecule(s)-“templated” calcification.

Hydraulic redistribution (HR) is a passive process in which water can move between wet and dry regions in the root zone by flowing through plant root systems. In this modeling study, we showed that adding HR to a process-based model improved soil moisture predictions, particularly in the top 30 cm. HR rates declined with increasing rainfall magnitude and frequency, but HR rates were also influenced by the length of dry spells between rainfall events.

Soil is a large pool of carbon storing globally, from 2 to 3 times more carbon than the atmosphere and vegetation. We measure the soil stock change from 2005 to 2019 at the ICOS crop site FR-Gri near Paris. The soil carbon stock decreased by approximately 72 ± 17 g C m^-2 yr^-1 over the period, resulting in a total loss of around 8% of the initial soil stock. This strong destocking is primarily attributed to a decrease in residue return and organic amendments to the site.