We examine seasonality of planktic foraminifera in an upwelling area to identify species vulnerable to changes in upwelling and ocean acidification and improve interpretation of fossil foraminifera. Of species associated with upwelling on the central California shelf, some are consistent with observations elsewhere while some associations appear to be unique to the region. All species show lunar periodicity and we confirm the presence of foraminifera at very low saturation state of calcite.

Global NPP and EP are reduced considerably for RCP8.5. Negative response of NPP and EP to stratification increases reflects a bottom-up control. Models with dynamic phytoplankton community structure show larger declines in EP than in NPP driven by phytoplankton community composition shifts. Projections of the NPP response to climate change depend on the phytoplankton community structure, the efficiency of the biological pump and the levels of regenerated production.

In the dry grassland investigated in this study the components of the soil CO₂ efflux decreased at different rates under drought conditions. During drought the contribution made by the heterotrophic components was the highest and the rhizospheric component was the most sensitive to soil drying. According to our results, the heterotrophic component of soil respiration is the major contributor to the respiration activities during drought events.

We use carbon isotopes of CO₂ to improve the performance of a land surface model, a component with earth system climate models. We found that isotope observations can provide important information related to the exchange of carbon and water from vegetation driven by environmental stress from low atmospheric moisture and nitrogen limitation. It follows that isotopes have a unique potential to improve model performance and provide insight into land surface model development.

Fen soils in northwest Germany are mainly intensively utilized for dairy farming. To estimate their climatic impact, the greenhouse gas exchange of four sites with different management intensity was measured using closed manual chambers. Results showed that long-term drainage intensity is more important for the global warming potential of fen soils than the type of management. Lowest yield-related emissions were achieved on a three-cut grassland with a high mean groundwater level.

We carried out a field experiment to evaluate the effect of replacing traditional winter fallow with cover crops (CCs) on greenhouse gas (GHG) emissions. Our results showed that the use of CCs should be recommended as a tool for reducing fertilizer nitrogen (N) input without increasing GHG losses – in the whole intercrop–maize cycle – or penalizing maize yields, if fertilizers are applied taking into account soil mineral N and N from CC residues.

An extensive compilation of published neodymium (Nd) concentrations and isotopic compositions (Nd IC) was realized in order to establish a new database and a map (using a high-resolution geological map of the area) of the distribution of these parameters for all the Mediterranean margins. The use of a high-resolution regional oceanic model (1/12° of horizontal resolution) allows us to realistically simulate for the first time the Nd IC distribution in the Mediterranean Sea.

We simulated mountain pine beetle (MPB) outbreaks under four scenarios for the presence and growth release strength of non-attacked vegetation, and found that: (1) impacts on ecosystem carbon and radiative forcing varied greatly across the four scenarios; (2) the global climatic impact from the current outbreak in British Columbia, Canada, seemed smaller than one month of anthropogenic CO₂ emissions; and (3) MPB-killed dead standing trees might hasten post-outbreak vegetation recovery.

We present clumped isotope data in air CO₂ over land and ocean in Taiwan and its vicinity. CO₂ over ocean is in thermodynamic equilibrium with the surface sea water and deviated significantly in urban and suburban areas due contribution from combustion emission. Photosynthetic activity deviates residual CO₂ from thermodynamic equilibrium but respiration does not. Deviations from thermodynamic equilibrium by various interactions in different environments are presented.

We compared growing season CO₂ fluxes of a wet tussock tundra ecosystem from an area affected by decadal drainage and an undisturbed area on the Kolyma floodplain in northeastern Siberia. The results show systematically reduced CO₂ uptake within the drained area, caused by increased respiration, and that the local permafrost ecosystem is capable of adapting to significantly different hydrologic conditions without losing its capacity to act as a net sink for CO₂.

By combining detailed geochemical analyses with diagenetic modeling, we provide new insights into how methane dynamics may strongly overprint burial records of iron, sulfur and phosphorus in marine systems subject to changes in organic matter loading or water column salinity. A better understanding of these processes will improve our ability to read ancient sediment records and thus to predict the potential consequences of global warming and human-enhanced inputs of nutrients to the ocean.

This paper presents new analyses conducted at high resolution in the Gulf of Cadiz over the last 50 ky. Palaeohydrological changes in these subtropical latitudes are discussed through dinoflagellate cyst assemblages but also dinocyst transfer function results, implying sea surface temperature and salinity as well as annual productivity reconstructions. This study is thus important for our understanding of past and future productivity regimes, also implying consequences on the biological pump.

In situ O₂ and pH measurements as well as determination of porewater concentrations of dissolved inorganic carbon, total alkalinity, sulfate and calcium have been measured in the sediments of the Rhône prodelta. Biogeochemical activity decreased with distance from the river mouth. Oxic processes decreased the carbonate saturation state (Ω) by lowering pH, whereas anaerobic organic matter degradation, dominated by sulfate reduction, was accompanied by increasing Ω and carbonate precipitation.

Nitrogen availability influences ecosystem properties and limits productivity in much of the world. We compared a variety of proxies used to assess nitrogen status to see if they provide consistent indications of nitrogen availability. We found that although terrestrial metrics correlated with one another, terrestrial and water-based metrics were not correlated. Given that many authors have suggested these proxies give insight into ecosystem nitrogen status, this result merits further research.

This paper aims to investigate the spatial variability in dissolved organic matter (DOM) in terms of both concentration and composition in the Congo River network. Stable carbon isotopes and absorption and fluorescent properties of DOM were used as proxies for DOM composition. This study shows that DOM degradation within the Congo Basin results in the transition from aromatic to aliphatic DOM as well as the role of landscape and water residence time on this transition.

Heavy storm events may increase the organic matter fluxes from forested watersheds and deteriorate water quality. Our study in two forested watershed in Korea revealed, that a larger proportion of coniferous forests likely leads to less organic carbon and larger of inorganic nitrogen fluxes to the receiving surface water bodies. More severe monsoon storms in the future will increase the fluxes of dissolved organic matter.