Recent  

A dune restoration project in the Northern Adriatic coast (Ravenna, Italy) was assessed using UAV monitoring surveys. SfM photogrammetry, elevation differencing, and statistical analysis were utilized to quantify dune development in terms of sand volume and vegetation cover change over time. Results show that the installed fence has been effective since there was significant sand accumulation, embryo dune development, and decrease in blowout features due to increased vegetation colonization.

Representing soil organic carbon (SOC) dynamics in Earth system models (ESMs) is a key source of uncertainty in predicting carbon climate feedbacks. We used machine learning to develop and compare predictive relationships in observations and ESMs. We found different relationships between environmental factors and SOC stocks in observations and ESMs. SOC predictions in ESMs may be improved by representing the functional relationships of environmental controllers consistent with observations.

For the first time, we documented the outstanding after-fire resilience of an invasive alien species, Saccharum biflorum, a rhizomatous C4 perennial grass introduced in the 19th century on the small volcanic island of Stromboli (Aeolian archipelago, Italy, Mediterranean Sea). Even if Saccharum biflorum prevails on native species in the early after-fire succession, it counteracts hydrogeological instability, paving the way to the recolonisation by native woody vegetation within a few decades.

Changes in the seasonality of primary production has been examined using daily data from two earth system models covering the period 1750–2100. The daily data made it possible to detect shifts in the day of the year during which the net primary production reaches its peak value. It was found that the day of peak primary production occurs earlier and earlier during the 21st century and that a major change in the time series occurs in the beginning of the 21st century.

In the Southern Ocean, abundant eddies behave opposite to our expectations. That is, anticyclonic (cyclonic) eddies are cold (warm). By investigating the variations of physical and biochemical parameters in eddies, we find that abnormal eddies have unique and significant effects on modulating the parameters. This study fills a gap in understanding the effects of abnormal eddies on physical and biochemical parameters in the Southern Ocean.

Fungus-growing termites recycle large part of dead plant material in African savannas and are significant sources of greenhouse gases. We measured CO₂ and CH₄ fluxes from their mounds and surrounding soils at open and closed habitats. The fluxes scale with mound volume. The results show that emissions from mounds of fungus-growing termites are more stable than those from other termites. The soil fluxes around the mound are affected by the termite colonies up to 2 m distance from the mound.

Ecosystem manipulative experiments are large experiments in real ecosystems. They include processes such as species interactions and weather which would be omitted in more controlled settings. They offer a high level of realism, but are underused in combination with vegetation models, used to predict the response of ecosystems to global change. We propose a workflow using models and ecosystem experiments together, taking advantage of the benefits of both tools for earth system understanding.

The taiga ecosystem in northeastern Siberia changed during the extreme wet event in 2007. Before the wet event, the NDVI in a typical larch forest showed a positive correlation with soil moisture, and after the event it showed a negative correlation. For both periods NDVI correlated negatively with foliar C/N. These results indicate that high soil moisture availability after the event decreased needle production, which may have resulted from lower N availability.

We conducted a meta-analysis of known experimental literature examining how marine bivalve growth rates respond to climate change. Bivalve growth is usually negatively impacted by climate change. Eggs/larval of bivalves are more vulnerable overall than either juveniles or adults. Available data on bivalve response to climate stressors are bias towards early growth stages, commercially important in the global north, and many families have only single experiments examining climate change impacts.

In our study, we assess the significance of methane (CH₄) emissions due to reservoir flushing. We generated a large dataset of CH₄ pore water concentrations in a reservoir's sediment to resolve seasonal CH₄ distributions in the sediment. Our results show that in the studied reservoir, CH₄ emissions caused by one flushing operation can represent 7–14 % of the annual CH₄ emissions and that timing and frequency of the flushing operations affect the amount of released CH₄.

Observations are used to reduce uncertainty in land surface models (LSMs) by optimising poorly-constraining parameters. However, optimising against current conditions does not necessarily ensure that the parameters treated as invariant will be robust under changing climate. Manipulation experiments offer us a unique chance to optimise our models under different (here atmospheric CO₂) conditions. By using these data in optimisations, we gain confidence in the future projections of LSMs.

This manuscript provides an overview of the capacity to expand the global coverage of marine primary production estimates using autonomous ocean-going instruments, called Biogeochemical-Argo floats. We review existing approaches to quantifying primary production using floats, provide examples of the current implementation of the methods, and offer insights into how they can be better exploited. This paper is timely, given the ongoing expansion of the biogeochemical Argo array.

Nitrogen (N) deposition to forest ecosystems is a matter of concern because it affects their nutrient status and make their soil acidic. We observed an ongoing acidification in a montane forest in central Switzerland even if the sub-soil of this site contains carbonates and is thus well-buffered. We experimentally added N to simulate a higher pollution and this increased the acidification. After 25 years of study, however, we can see first signs of recovery, also in under higher N deposition.

Ocean deoxygenation due to climate warming is an evolving threat for organisms that are not well adapted to O₂ depleted conditions, such as many pelagic fish species. Other better adapted organisms, such as benthic foraminifera, might benefit from ocean deoxygenation. Benthic foraminifera are a group of marine protists and can have specific adaptations to O₂ depletion such as the ability to respire nitrate instead of O₂. This paper reviews the current state of knowledge about these organisms.

As the ocean absorbs 25 % of the anthropogenic emissions of carbon, it is important to understand the impact of climate change on the flux of carbon between the ocean and the atmosphere. Here, we use a very high-resolution ocean, sea-ice, carbon cycle model to show that the capability of the Southern Ocean to uptake CO₂ has decreased over the last 50 years due to a strengthening and poleward shift of the southern hemispheric westerlies. This trend is expected to continue over the coming century.

Permafrost thaw in Arctic regions is increasing methane emissions but quantification is difficult given the large and remote areas impacted. We show that drone data together with satellite data can be used to extrapolate emissions across the wider landscape as well as detecting areas at risk of higher emissions. A transition of currently degrading areas to fen type vegetation can increase emission with several orders of magnitude highlighting the importance of quantifying areas at risk.

Chromophore dissolved organic matter (CDOM) interact with the ambient light and gives the waters of the Mediterranean Sea their colour. We propose a novel parameterisation of the CDOM cycle, whose parameter values have been optimized by using the data of the monitoring site BOUSSOLE. Nutrient and light limitations for locally-produced CDOM caused α_CDOM(λ) to covary with chlorophyll, while the above-average CDOM concentrations observed at this site were maintained by vertically transported CDOM.

Nitrogen is important for plant growth and carbon uptake, which is uaually limited in nature and can constrain carbon storage and impact efforts to combat climate change. We developed a new method of combining data and models to determine if and how much an ecosystem is nitrogen limited. This new method can help determine if and to what extent an ecosystem is nitrogen-limited, providing insight into nutrient limitations on a global scale and guiding ecosystem management decisions.

Modelling the ocean's carbon and oxygen cycles accurately is challenging. Parameter optimization improves the fit to observed tracers but can introduce artifacts in the biological pump. Organic-matter production and subsurface remineralization rates adjust to compensate for circulation biases, changing the pathways and timescales with which nutrients return to the surface. Circulation biases can thus strongly alter the system’s response to ecological change, even when parameters are optimized.

Oxygen availability in marine and freshwater is very variable at daily and seasonal scale. The dynamic nature of oxygen fluctuations has important consequences for the animal and microbes physiology and ecology, yet fully understood. With this contribution, we showed the heterogeneous nature of aquatic oxygen landscape, that here we defined as “oxyscape”, and we addressed its importance that need be considered in the modelling and managing aquatic ecosystems.

According to investigations in central and western China. It shows that tree ring Inverse latewood intensity expresses a strong positive relationship with growing season temperatures, indicating exciting potential for regions south of 30° N that are traditionally not targeted for temperature reconstructions. Earlywood BI also shows good potential to reconstruct hydroclimate parameters in some humid areas and will enhance ring-width based hydroclimate reconstructions in the future.

A higher understanding of O₂ fluxes, their exchange ratios with CO₂ and their interrelations with environmental conditions would provide further insights in biogeochemical ecosystem processes. We, therefore, used the multi-layer canopy model, CANVEG, to simulate and analyze the flux exchange for our forest study site for 2012–2016. Based on these simulations, we further tested successfully the application of various micrometeorological methods and the prospects of real O₂ flux measurements.

This review argues towards the integration of microwave spaceborne information in carbon cycle science for Arctic-boreal regions. The microwave data record spans multiple decades with frequent global observations of soil moisture and temperature, surface freeze/thaw cycles, vegetation water storage, snowpack properties and land cover. This record holds substantial unexploited potential to better understand carbon cycle processes.

Twenty tropical tree species native to Africa was planted along an elevation gradient (1100 m, 5.4 °C difference). We found that early successional (ES) species, especially from lower elevations, grew faster at warmer sites while several of the late successional (LS) species, especially from higher elevations, did not respond or grew slower. Moreover, a warmer climate increased tree mortality in LS species, but not much in ES species.

The microbial-explicit model – CLM-Microbe – was first applied to investigate the carbon cycle in terrestrial ecosystems. The simulated carbon storages and fluxes are consistent with previous estimates. The bacterial and fungal biomass carbon showed increasing trends from 1901 to 2016, with large spatial variations. The long-term global estimation of microbial dynamics provides a quantitive understanding of microbial contributions to the global carbon cycle.

We examine the impacts of multi-decadal nitrogen additions on a dryland ecosystem N budget, including the soil, microbial and plant N pools. After 26 years, there appears to be little impact on the soil microbial or plant community and only minimal increases in N pools within the soil. While perhaps encouraging from a conservation standpoint, we calculate that greater than 95 % of the nitrogen added to the system is not retained and is instead either lost deeper in the soil or emitted as gas.

We compared soil model performance to data from a long-term nitrogen addition experiment in a forested ecosystem. We found that in order for soil carbon models to accurately predict future forest carbon sequestration, two key processes must respond dynamically to nitrogen availability: (1) plant allocation of carbon to wood versus roots, and (2) rates of soil organic matter decomposition. Long-term experiments can help improve our predictions of the land carbon sink and its climate impact.

Marbles in the desert areas of Namibia and Oman were found to be consumed from inside the rock mass by microbiological activity of a thus far unknown nature that created bands of parallel tubules. These bands formed along fractures in the rock and only surfaced after erosion made them visible. We consider this a new niche for life that has so far not been described. These life forms may have an unknown impact on the global carbon cycle.

Land-use changes can affect water quality. We used tracers of pollution sources and water flow paths to show that an urban watershed exports variable sources during storm events relative to a less developed watershed. Our results imply that changing precipitation patterns combined with increasing urbanization may alter sources of pollution in the future.

We identified total soil P as the most important predictor of all soil P pool concentrations, except for primary mineral P concentration, which is primarily controlled by soil pH. We found soil pH is the most important predictor for proportions of all soil P pools, except for labile Pi proportion, which is primarily controlled by soil depth. We predicted soil P pools’ distributions in natural systems at a resolution of 0.5° × 0.5°.

Shallow lakes and ponds undergo frequent stratification in the summer months. Here we studied how this effect the greenhouse gas (GHG) emissions. We found that stratification caused anoxia in the bottom waters driving increased GHG emissions, in particular methane released as bubbles. In addition methane and carbon dioxide accumulated in the bottom waters during stratification leading to large emissions when the lake mixed again.