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To mitigate our impact on the climate, research suggests that we will need to both drastically reduce emissions and perform carbon dioxide removal (CDR). We simulated future climates under three emissions scenarios, in which we removed some carbon from the air and put it into agricultural soil at varying rates. We found that agricultural CDR is much more effective at reducing global temperatures if done in a low emissions scenario and at a high rate, and it becomes less effective with time.

Accurate radiation data are essential for understanding ecosystem growth. Traditional large-scale data lack the precision needed for complex terrains, e.g. mountainous regions. This study introduces a new model to enhance radiation data resolution using elevation maps, which accounts for sub-daily direct and diffuse radiation effects caused by terrain features. Tested on Mont Ventoux, this method significantly improves radiation estimates, benefiting forest growth and climate risk models.

The laws of physics show that leaf oxygen is not photosynthetically enriched, but extremely dilute due to the overwhelming effects of humidification. This challenges the prevailing diffusion-only paradigm regarding leaf gas exchanges, requiring non-diffusive transport. Such transport also explains why fluxes of carbon dioxide and water vapour become decoupled at very high temperatures, as has been observed but not explained by plant physiologists.

This article presents data on iron and manganese, which are essential micronutrients for primary producers, on the surface of the Arctic’s Laptev and East Siberian Seas (LESS). Observations were made in international cooperation with the NABOS expedition during the late summer of 2021 in the Arctic Ocean. The results from this study indicate that the major factors controlling these metal concentrations in LESS are river discharge and the input of shelf sediment.

We measured soil carbon fluxes during the first four years after a wildfire in the Swedish boreal forest. Soil CO₂ emissions decreased substantially only when trees were killed by fire or by post-fire logging, but not when trees survived the fire and were left standing. Soil methane flux was not affected by fire. Logging trees already killed by fire had no additional impact on soil carbon fluxes. Post-fire forest management strategy impacted vegetation regrowth and carbon dynamics.

This study analyzed marine sediment samples from areas with and without minimal hydrocarbon seepage from reservoirs underneath. Depth profiles of dissolved chemical components in the pore water as well as molecular biological data revealed differences in microbial community composition and activity. These results indicate that even minor hydrocarbon seepage affects sedimentary biogeochemical cycling in marine sediments, potentially providing a new tool for detection of hydrocarbon reservoirs.

In our study, we assessed the impact of olivine on marine primary producers of ocean-based solutions. The experiments revealed no negative effects on carbon fixation rates. Additions of the alkaline minerals did not establish growth inhibition; instead, they showed slight growth increases with species-specific responses. Ni exposure from olivine did not inhibit growth. However, limitations include the absence of responses in natural settings.

Mountain grasslands are impacted by Climate Change and need to adapt. Low mountain grasslands are poorly understood compared to High Mountains massif. Thanks to satellite archives, we found that grasslands occurring in the Vosges Mountains (France) exhibited stable productivity or tended to decrease in specific regions of the massif, a reverse signal observed in High Mountains massif. We also noted a high responsiveness in their growth strategy to soil moisture, snow regimes and topography.

Our results showed that crop development derived from satellite images was lower in a dry year compared to a normal year, and faster growth was found more important for higher biomass during drought. The magnitude of the drought impact differed between fields, where higher crop performance was related to more plant available water, suggesting that soil properties play a role in crop response to drought. Our results shows that satellite images can be used to assess plant-soil-weather interactions

Phytoplankton net primary production (NPP) is influenced by many processes, and their representation varies across Earth-system models. This leads to differing projections for NPP's future under climate change, especially in the North Atlantic. To address this, we identified and assessed the processes controlling NPP in each model. This assessment helped us select the most reliable models, significantly improving NPP projections in the region.

The open ocean helps mitigate climate change by storing CO₂ through the biological carbon pump (BCP). The BCP involves processes like phytoplankton capturing CO₂ and sequestering it in the deep ocean via marine snow production. We found significant marine snow accumulation from the surface to 600 meters deep in frontal regions between eddies. We suggest that the coupling of hydrodynamics at eddy edges and biological activity (via planktonic organisms) may enhanced this process.

The present study reports Fe-Mn-driven anaerobic oxidation of methane (Fe-Mn-AOM) in seasonally hypoxic coastal sediments under sulfidic conditions. The Fe-Mn-AOM activity is observed over the entire sediment core at multiple depths above and below the sulfate methane transition zone. We hypothesize that the focused Fe-Mn-AOM activity is possibly controlled by the Fe-Mn reducing microbial population distribution in the sediment core.

Gamma A is a widespread non-cyanobacterial diazotroph and plays a crucial role for marine ecosystems, but its controlling factors are still largely unknown. This study, for the  first time, quantified microzooplankton grazing on Gamma A and revealed significance of grazing pressure on Gamma A distribution around the Kuroshio region. It highlights the importance of top-down controls on Gamma A abundance and the associated nitrogen cycle.

The environmental factors and CO₂ flux of the grassland ecosystem in the dry-hot valley of the Jinsha River exhibited highly seasonal characteristics. During the rainy season, the grassland showed a carbon sink feature, while during the dry season, it exhibited carbon emission status. Throughout the entire year, the grassland ecosystem acted as a weak carbon source, exhibiting a carbon-neutral. The CO₂ flux was most influenced by vapor pressure deficit, relative humidity, and soil water content.

Coastal and shelf sediments are the most important sinks for organic carbon (OC) on Earth. We produced a new high-resolution sediment and pore-water dataset from the Helgoland Mud Area (HMA), North Sea, to determine, which depositional factors control the preservation of OC. The burial efficiency is highest in an area of high sedimentation and terrigenous OC. The HMA covers 0.09 % of the North Sea, but accounts for 0.76 % of its OC accumulation, highlighting the importance of the depocentre.

Intense grazing at grassland sites removes vegetation, reduces the snow cover, and inhibits litter layers from forming. Grazed sites generally have a larger annual ground surface temperature amplitude than ungrazed sites, but the net effect depends on effects in the transitional seasons. Our results also suggest that seasonal use of pastures can reduce ground temperatures, which can be a strategy to protect currently degrading grassland permafrost.

When microbes consume carbon within soils, it is important to know how much carbon is respired and lost as carbon dioxide versus how much is used to make new biomass. We used a new approach of monitoring carbon dioxide and oxygen to track the fate of consumed carbon during a series of laboratory experiments where sugar was added to moistened soil. Our approach allowed us to estimate how much sugar was converted to dead microbial biomass, which is more likely to be preserved in soils.

This study explores the impact of environmental conditions on the chemistry of coccoliths, calcite minerals produced by marine algae, to better understand past climate changes. By cultivating different species of coccolithophores under various CO₂ and pH levels, we have shown that the isotopic composition of certain species varies with CO₂ concentration and quantified these variations.

Here we present a comparison of results from the Mg/Ca and oxygen stable isotopes paleothermometers obtained from 57 modern to fossil species of planktonic foraminifera from the last 15 million of years. We find that the occurrence (or not) of species-species offsets in Mg/Ca is conservative between ancestor-descendent species, and that taking into account species kinship can significantly improve temperature reconstructions by several degrees.

Estuarine marshes are vital for capturing carbon and benefiting the climate. Our research explored how plant-microbe interactions affect carbon cycling, focusing on traits like root oxygen loss. Using a model, we found that accounting for these trait variations significantly changes carbon balance estimates. This suggests that including plant diversity in ecosystem models improves predictions about carbon dynamics in estuarine marshes, highlighting their importance in climate regulation.

Inland saline lakes are crucial in the global carbon cycle, but increased droughts may alter their carbon exchange capacity. We measured CO₂ and CH₄ fluxes in a Mediterranean saline lake using the Eddy Covariance method under dry and wet conditions. We found the lake acts as a carbon sink during wet periods but not during droughts. These results highlight the importance of saline lakes in carbon sequestration and their vulnerability to climate change-induced droughts.

A long-term pH variation in coastal waters along the Korean peninsula was assessed for the first time, and it exhibited no significant pH change over an 11-year period. This contrasts with the ongoing pH decline in open oceans and other coastal areas. Analysis of environmental data showed that pH is mainly controlled by dissolved oxygen in bottom waters. This suggests that ocean warming could cause a pH decline in Korean coastal waters, affecting many fish and seaweeds aquaculture operations.

We measured concentrations of fallout radionuclides (FRNs) in soil samples taken from arable land in South Africa. We find that during the second half of the 20^th century CE, the FRN data strongly correlate with the soil organic matter (SOM) content of the soils. The finding implies that wind erosion strongly influenced SOM loss in the soils we investigated. Furthermore, the exponential decline of FRN concentrations and SOM content over time peaks shortly after native grassland is cultivated.

This study exposed a natural community to two non-CO₂ equilibrated ocean alkalinity enhancement (OAE) deployments using different minerals. Adding alkalinity in this manner decreases dissolved CO₂, essential for photosynthesis. While photosynthesis was not suppressed, bloom formation was delayed, potentially impacting marine food webs. The study emphasizes the need for further research on OAE without prior equilibration and its ecological implications

Methane emissions from Lake Kortowskie were monitored from 2019 to 2022, alongside the collection of water and meteorological data. Annual differences of CH₄ emissions were relatively low (mean 11.79 mg m^-2 d^-1), but there were significant seasonal variations. The main factors associated with CH₄ emissions were temperature, water agitation, wind, precipitation, Secchi depth, and oxygen concentration. Data analyses suggest an increase in CH₄ emissions from the lake by over 30 % by the year 2100.

The distribution of N₂O in fjord-like estuaries is poorly described in the southern hemisphere. Our study describes N₂O distribution and its drivers in one such system Macquarie Harbour, Tasmania. Water samples were collected seasonally from 2022/2023. Results show the system is a sink for atmospheric N₂O when river flow is high; and the system emits N₂O when the river flow is low. N₂O generated in basins is intercepted by the surface water and exported to the ocean during high river flow.

We present a fully automatic, low-cost soil-plant enclosure system to monitor CO₂ and ET fluxes within greenhouse experiments. It operates in two modes: independent, using low-cost sensors, and dependent, connecting multiple chambers to a single gas analyzer via a low-cost multiplexer. This system offers precise and accurate measurements, cost and labor efficiency, and high temporal resolution, enabling comprehensive monitoring of plant-soil responses to various treatments and conditions.

This study questions the usefulness of state-ot-the-art models to characterize the temporal variability of atmosphere-ecosystem CO₂ exchanges in western European forests. Their mean annual cycle and annual budget are better captured by statistical than physical models, while their interannual variability and long-term trend are better captured by models forced by climate variability. Accounting for both forest stands and climate variability is thus key for properly assessing CO₂ fluxes.

In a multilayered approach, we studied eight cut and buried abandoned oil wells in a peat rich area of Northern Germany for methane flux, soil gas composition, and isotopic signatures of soil methane and carbon dioxide. The detected methane emissions were of biogenic, peat origin and were not associated with the abandoned wells. Additional microbial analysis and methane oxidation rate measurements demonstrated a high methane-emission mitigation potential in the studied peat-soils.

Nitrate is a crucial nutrient in oceans. Excess nutrients can trigger uncontrolled algae growth (eutrophication), damaging marine ecosystems. We used a machine learning tool to generate a skilled, gap-free, bi-decadal surface nitrate dataset from sparse observations. This dataset reveals areas on the North West European Shelf at risk of eutrophication, bi-decadal trends in coastal nitrate, and an impact of winter nitrate on spring phytoplankton blooms.

Coastal enhanced silicate weathering (CESW) with olivine is a promising method for capturing CO₂ from the atmosphere, yet studies in field conditions are lacking. We bridge the gap between theoretical studies and the real-world environment by estimating the predictability of CESW parameters and identifying aspects to consider when applying CESW. A major source of uncertainty is the lack of experimental studies with sediment, which can heavily influence the speed and efficiency of CO₂ drawdown.

Archaeal hydroxylated tetraether lipids are increasingly used as temperature indicators in marine settings, but the factors influencing their distribution are still unclear. Analyzing membrane lipids of two Thaumarchaeotal strains showed that the growth phase of the cultures does not affect the lipid distribution, but growth temperature profoundly affects the degree of cyclization of these lipids. Also, the abundance of these lipids is species-specific and is not influenced by temperature.