To obtain magnitudes of flux components of H₂O and CO₂ (e.g., transpiration, soil respiration), we applied source partitioning approaches after Scanlon and Kustas (2010) and after Thomas et al. (2008) to high-frequency eddy covariance measurements of 12 study sites covering various ecosystems (croplands, grasslands, and forests) in different climatic regions. We analyzed the interrelations among turbulence, site characteristics, and the performance of both partitioning methods.

In stony deserts, when rocks are exposed to atmospheric conditions, they undergo weathering. The cavernous (honeycomb) weathering pattern is one of the most common, but it is still unclear exactly how it is formed. We show that microorganisms, which differ from the surrounding soil and dust, form biological crusts on exposed rock surfaces. These microbes secrete polymeric substances that mitigate weathering by reducing evaporation rates and, consequently, salt transport rates through the rock.

Seawater salinity is an important factor when trying to reconstruct past ocean conditions. Foraminifera, small organisms living in the sea, produce shells that incorporate more Na at higher salinities. The accuracy of reconstructions depends on the fundamental understanding involved in the incorporation and preservation of the original Na of the shell. In this study, we unravel the Na composition of different components of the shell and describe the relative contribution of these components.

We present rare data on the combined effects of acidification and warming on dimethylsulfide (DMS) during a mesocosm experiment. Our results show a reduction of DMS under elevated pCO2, but warming the mesocosms by 5 °C translated into a positive offset in concentrations of DMS over the whole range of pCO2 tested. Our results suggest that warming could mitigate the expected reduction in DMS production due to OA, even increasing the net DMS production, with possible repercussions for the climate.

Soil water is a medium from which microbes acquire resources and within which they are able to move. Occupancy and availability of water and oxygen gas in soils are mutually exclusive. In addition, as soil dries the remaining water is held with an increasing degree of adhesive energy, which restricts microbes' ability to extract resources from water. We introduce a mathematical model that describes these interacting effects and organic matter decomposition.

How fast might the arctic treeline in northern central Siberia migrate northwards under current global warming? To answer this, we newly parameterized dispersal processes in the individual-based and spatially explicit model LAVESI-WIND based on parentage analysis. Simulation results show that northernmost open forest stands are migrating at an unexpectedly slow rate into tundra. We conclude that the treeline currently lags behind the strong warming and will remain slow in the upcoming decades.

Predicting how soils respond to varying environmental conditions or land-use change is essential if we aim to promote sustainable management practices and help mitigate climate change. Here, we present a new ecosystem-scale soil model (MEMS v1) that is built upon recent, novel findings and can be run using very few inputs. The model accurately predicted soil carbon stocks for more than 8000 sites across Europe, ranging from cold, wet forests in sandy soils to hot, dry grasslands in clays.

The biological carbon pump, the process by which carbon-laden particles sink out of the surface ocean, is dynamic and fast. The use of autonomous observations will better inform carbon export simulations. The Carbon Flux Explorer (CFE) was developed to optically measure hourly variations of particle flux. We calibrate the optical measurements of the CFE against C and N flux using samples collected during a coastal California cruise in June 2017. Our results yield well-correlated calibrations.

By comparing the cork oak tree vegetative phenology in two contrasting precipitation years in a Mediterranean ecosystem, we showed the critical role of water availability in extending the length of the growing season and determining tree growth. The observed higher transfer of nitrogen from senescent to green leaves in response to drought might compensate for the limited nitrogen uptake by the roots. Our results improve our understanding of the ecosystem's responses to climate change.

We review and synthesize available information on coastal ocean carbon fluxes around North America (NA). There is overwhelming evidence, compiled and discussed here, that the NA coastal margins act as a sink. Our synthesis shows the great diversity in processes driving carbon fluxes in different coastal regions, highlights remaining gaps in observations and models, and discusses current and anticipated future trends with respect to carbon fluxes and acidification.

Iron analysis of the particulate, colloidal, and truly dissolved fractions along the Lena River freshwater plume showed that the particulate iron dominates close to the coast. Over 99 % particulate and about 90 % colloidal iron were lost, while the truly dissolved phase was almost constant. Iron isotopes suggest that the shelf acts as a sink for particles and colloids with negative iron isotope values, while colloids with positive iron isotope values travel further out into the Arctic Ocean.

As commonly observed in oligotrophic stratified waters, a subsurface (or deep) chlorophyll maximum (SCM) frequently characterizes the vertical distribution of phytoplankton chlorophyll in the Mediterranean Sea. SCMs often result from photoacclimation of the phytoplankton organisms. However they can also result from an actual increase in phytoplankton carbon biomass. Our results also suggest that a variety of intermediate types of SCMs are encountered between these two endmember situations.

This study examined rainforest responses to elevated CO₂ coming from volcanoes in Costa Rica. Comparing tree species, we found that leaf function responded when exposed to increasing CO₂ levels. The chemical signature of volcanic CO₂ is different than background CO₂. Trees exposed to volcanic CO₂ also had chemical signatures which showed the influence of volcanic CO₂: trees not only breathe in and are made of volcanic CO₂ but also retain that exposure history for decades.

This work reports the consequences of nutrient management strategy, an example from southwestern Europe focused mainly on P reduction. Upstream rivers reveal indices of recoveries following the significant diminution of P, while eutrophication continues to increase downstream, especially when N is the limiting factor. This long-term ecosystem-scale analysis provides more arguments for a dual-nutrient (N and P) management strategy to mitigate eutrophication along the freshwater–marine continuum.