Recent  

Subduction transports surface waters to the oceanic interior, which can supply significant amounts of carbon and oxygen to the twilight zone. Using a novel BGC-Argo dataset covering the western North Pacific, we successfully identified the imprints of episodic shallow subduction patches. These subduction patches were observed mainly in spring and summer (70.6 %), and roughly half of them extended below ~450 m, injecting carbon- and oxygen-enriched waters into the ocean interior.

Uncertainty in the response of photosynthesis to temperature poses a major challenge to predicting the response of forests to climate change. In this paper, we study how photosynthesis in a mountainous evergreen forest is limited by temperature. This study highlights that cold temperature is a key factor that controls spring photosynthesis. Including the cold temperature limitation in an ecosystem model improved its ability to simulate spring photosynthesis.

Oxygen flux across the sediment surface provides key information regarding ecosystem function, but present measuring techniques produce relatively large error ranges. We developed a new eddy covariance instrument that substantially improves the precision of oxygen flux measurements and deployed it over coral reef sands. Measured fluxes ranged among the highest reported for marine sediments, indicating a central role of microalgae for the cycles of matter in the sand and for coral reef health.

This study shows that grassland vegetation management (livestock grazing, grass cutting) determines whether a grassland is adding (source) or removing (sink) carbon (C) to/from the atmosphere. The annual C balance of 1855 managed grassland fields in Great Britain was quantified for 2017–2018. The examined fields were, on average, small C sinks but the summer drought of 2018 led to a 9-fold increase in the number of fields that became C sources in 2018 compared to 2017.

Saharan dust deposition of nutrients and trace metals is crucial to microbes in the Mediterranean Sea. Here, we tested the response of microbial and viral communities to simulated dust deposition, under present and future conditions of temperature and pH. Overall, the effect of deposition was dependent on the initial microbial assemblage, and future conditions will intensify microbial responses. We observed effects on trophic interactions cascading all the way down to viral processes.

Ammonium is a crucial yet poorly-understood component of the Southern Ocean nitrogen cycle. We attribute our finding of consistently high ammonium concentrations in the winter mixed layer to limited ammonium consumption and sustained ammonium production, conditions under which the Southern Ocean becomes a source of carbon dioxide to the atmosphere. From similar data collected over an annual cycle, we propose a seasonal cycle for ammonium in shallow polar waters – a first for the Southern Ocean.

This study tested combinations of two sources of AGB data and two sources of LCC data, and used the same burned area satellite data to estimate BB CO emissions. Our analysis showed large discrepancies in annual mean CO emissions and explicit differences in the simulated CO concentrations among the BB emissions estimates. This study has confirmed that BB emissions estimates are sensitive to the land surface information on which they are based.

Arctic permafrost ecosystems may release large amounts of carbon under warmer future climates, and may therefore accelerate global climate change. Our study investigated how long-term grazing by large animals influenced ecosystem characteristics and carbon budgets at a Siberian permafrost site. Our results demonstrate that such management can contribute to stabilize ecosystems to keep carbon in the ground, particularly through drying soils and reducing methane emissions.

Western rock lobster larvae spend up to 11 months in offshore waters before ocean currents and their ability to swim, transport them back to the coast. In 2008, there was reduction in the number of puerulus (larvae) settling into the fishery. We use an oceanographic model to see how the environment may have contributed to the reduction. Our results show that a combination of effects from local currents and wide-spread “quiet” period in the ocean off WA likely lead to less puerulus settlement.

Here we present a new modelling framework, specifically designed to simulate alluvial peat growth, taking into account the river dynamics. The results indicate that alluvial peat growth is strongly determined by the number, spacing and movement of the river channels in the floodplain, rather than by environmental changes or peat properties. As such, the amount of peat that can develop in a floodplain is strongly determined by the characteristics and dynamics of the local river network.

The purpose of this paper is to (1) to implement angiosperm paleo-traits in a land-surface model according to the fossil record, (2) assess this paleo-vegetation functioning under different pCO₂. We show that photosynthesis, transpiration and water-use efficiency are dependent on both the vegetation parameterization and the pCO₂. Comparing the modeled vegetation with the fossil record, we provide clues on how to account for angiosperm evolutionary traits in paleoclimate simulations.

Previous studies show that phytoplankton light absorption can warm the atmosphere via an increase in air-sea heat exchange and CO₂ flux. Which of this flux is the main driver in the phytoplankton-induced atmospheric warming is still unknown. To shed light on this research question, we conduct simulations with a climate model of intermediate complexity. We show that phytoplankton mainly warms the atmosphere by increasing the air-sea CO₂ flux.

Benthic foraminifera play a significant role in modern reefal ecosystems mainly due to their symbiosis with photosynthetic microorganisms. Foraminifers were also components of Devonian stromatoporoid-coral reefs however, whether they could have harbored symbionts remained unsolved. We show that Devonian foraminifers might have stayed photosynthetically active what likely had an impact on their evolutionary radiation and possibly also on the functioning of Palaeozoic shallow-marine ecosystems.

We took the water cycle process of soil-plant-atmospheric precipitation as the research objective. In the water cycle of soil-plant-atmospheric precipitation, precipitation is the main controlling role. The main source of replenishment for alpine meadow plants is precipitation and alpine meltwater, the main source of replenishment for forest plants is soil water, and the plants in the arid foothills mainly use groundwater.

The bacterial mineralization of dissolved organic matter (DOM) in inland waters contributes to CO₂ emissions to the atmosphere. Human activities affect DOM sources, however the implications on DOM mineralization are poorly known. Combining sampling and incubations, we showed that higher bacterial respiration in agro-urban streams related to a labile pool from aquatic origin. Therefore, human activities may have a limited impact on the net carbon exchanges between inland waters and atmosphere.

Here, we synthesize the results from 62 studies reporting in situ rates of seagrass metabolism to highlight spatial and temporal variability in carbon fluxes and inform efforts to use seagrass to mitigate ocean acidification. Our analyses suggest seagrass meadows are generally autotrophic, variable in space and tie, and the modeled effects on seawater pH are relatively small in magnitude.

The permafrost soils hold about twice as much carbon as the atmosphere, as the Earth warms the organic matter in these soil will decay releasing CO₂ and CH₄. It is expected that these soil will continue to release carbon into the atmosphere long after emissions cease. Here we use a method where hundreds of slightly varying model versions to estimate how much warming permafrost carbon will cause after human emissions of CO₂ end.