We used a process-based model to investigate the sensitivities of pan-Arctic wetland methane emissions to climate factors, as a function of climate. Over the period 1960-2006, temperature was the dominant driver of trends in emissions. Wetlands north of 60N were temperature-limited, and wetlands south of 60N latitude were water-limited. Projected future warming will cause water-limited wetlands to expand northward over the next century, lessening the role of temperature in the future.

The governing parameter of DOC and major element concentrations and fluxes in western Siberia is latitude. High fluxes in the continuous permafrost zone of frozen peat bogs stem from the fact that the underlining mineral layer is not reactive, protected by the permafrost so that the major part of the active layer is located within the organic (peat) matrix and not the mineral matrix. Possible changes in export fluxes of DOC and major river water components under permafrost thaw are quantified.

We investigate variability in surface ocean carbonate chemistry using output from a 1000-year control simulation of an Earth System Model. We find that the detection timescale for trends is strongly influenced by the variability. As the scientific community seeks to detect the anthropogenic influence on ocean carbonate chemistry, these results will aid the interpretation of trends calculated from spatially and temporally sparse observations.

Fungi in the atmosphere can affect precipitation by nucleating the formation of clouds and ice. This process is important over the Amazon rainforest where precipitation is limited by the types and amount of airborne particles. We found that the total and metabolically active fungi communities were dominated by different taxonomic groups, and the active community unexpectedly contained many lichen fungi, which are effective at nucleating ice.

Sun-induced chlorophyll fluorescence and photochemical reflectance index revealed controls of climate and nutrient availability on photosynthesis (gross primary production, GPP). Meteo-driven models (MMs) were unable to describe nutrient-induced effects on GPP. Important implications can be derived from these results, and uncertainties in the prediction of global GPP still remain when MMs do not account for plant nutrient availability.

This manuscript covers the first measurements of CHBr3, CH2Br2 and CH3I from the equatorial Atlantic during the Cold Tongue season, identifying this region and season as a source for these compounds. For the first time, we calculated diapycnal fluxes, and showed that the fluxes from below the mixed layer to the surface are not sufficient to balance the mixed layer budget. Hence, we conclude that mixed layer production has to take place despite a pronounced sub-mixed-layer-maximum.

Stoichiometry of macronutrients in the subtropical ocean is important to understand how biogeochemical cycles are coupled. We observed that elemental stoichiometry was much higher in the dissolved organic-matter pools than in the particulate organic matter pools. In addition ratios vary with depth due to changes in growth rates of specific phytoplankton groups, namely cyanobacteria. These data will improve biogeochemical models by placing observational constraints on these ratios.

The prediction of the greenhouse gas N2O from natural soils globally is sensitive to the representation of soil water. Factors that regulate nitrogen retention and nitrogen limitation, including fire and biological nitrogen fixation are further influencing the N2O gas production. Responses to warming and CO2 increase are strongly controlled by tropical soils. Therefore extrapolation of mostly extra-tropical field studies the globe warrants caution.

The ongoing increase in anthropogenic carbon dioxide (CO2) emissions is changing the environment. Reduction of CO2 to a sustainable level is required to avoid further change. In this manuscript, the carbon storage potential of coralline algae (CA) and their deposits is accessed. We show that CA represent an as yet unquantified significant carbon repository, storing similar amounts of carbon to seagrasses and mangroves. Critically, stored carbon will likely be stable at geological timescale.

Overall P content increased with decreasing size of soil aggregate-sized fractions. The relative distribution and speciation of varying P forms were independent of particle size. The majority of alkaline extractable P was in the amorphous Fe/Al oxide fraction, most of which was orthophosphate. Significant amounts of monoester P were also bound to these oxides. Residual P contained similar amounts of P occluded in amorphous and crystalline Fe oxides. This P may be released by FeO dissolution.

The recovery of a basket star in 1818 from deep waters of Baffin Bay is often cited as the first organism that was brought up from the deep sea. Yet recoveries of stalked crinoids from the Caribbean and catches of several bathyal fishes occurred decades earlier. However, these accidental catches remained largely neglected during the 19th and 20th century because the bathyal nature of these animals was not recognized, and because they were not tied to a known water depth.

Atmospheric deposition of inorganic fixed nitrogen has been evaluated and quantified for the Black Sea at different spatial and temporal scales. The effect of this deposition has appeared comparable to riverine load of nutrients. This atmospheric deposition can dramatically increase primary production with the major effects for off-shore regions. It does support the currently highly eutrophic state of the Black Sea and prevents rehabilitation of this ecosystem.

The White Cliffs of Dover date back to the Cretaceous and are made up of microscopic chalky shells which were produced mainly by marine phytoplankton (coccolithophores). This is iconic proof for their success at times of relatively high seawater calcium concentrations and, as shown here, to be linked to their ability to precipitate calcium as chalk. The invention of calcification can thus be considered an evolutionary milestone allowing coccolithophores to thrive at times when others struggled.

The study focuses on co-digestion of food waste and its derivatives i.e. noodle waste and rice waste with sludge in order to produce bio-hydrogen. The pH was set at 7 initially and was not controlled throughout the incubation in order to make the process simple. Noodle waste produced maxim bio-hydrogen production as compared to food waste and rice waste. The increase in temperature increased the bio-hydrogen production for food waste but caused negative impact on noodle and rice wastes.

Primary production, NO3- and NH4+ uptake, and nitrification rates were measured during the KEOPS 2 cruise (austral spring 2011) in the Kerguelen Plateau area. Natural iron fertilization stimulated primary production which is much higher in the fertilized areas compared to the HNLC site. We report high rates of nitrification in the mixed layer below the euphotic zone. We conclude that high productivity in deep mixing system stimulates the N cycle by increasing both assimilation and regeneration.