Using night fire detection and rainfall datasets during 1997–2015, we found that the number of night fires detected in 1997 was 2.2 times higher than in 2015, but with a higher fraction of peatland burned in 2015. We also confirmed the non-linearity of rainfall accumulation prior to a fire to indicate a high fire year. The influence of rainfall on the number of yearly fires varies across Indonesia. Southern Sumatra and Kalimantan need 120 days of observations, while northern Sumatra only 30.

Neutral carbohydrates, carbon isotopic composition, and algal productivity proxies in three reservoir sediment cores, South China, were investigated. Monosaccharide compositions and diagnostic parameters indicate a predominant contribution of phytoplankton in the sediment cores. Algal monosaccharide content is highly related to the algal productivity and increasing mean air temperature, but not to nutrient input, demonstrating the effect of climate warming in low-latitude regions.

We employed an individual- and patch-based dynamic global ecosystem model to quantify long-term C accumulation rates and to assess the effects of historical and projected climate change on peatland C balances across the pan-Arctic. We found that peatlands in Scandinavia, Europe, Russia and central and eastern Canada will become C sources, while Siberia, far eastern Russia, Alaska and western and northern Canada will increase their sink capacity by the end of the 21st century.

Leaf scale measurements have been performed on English oak, European beech and Norway spruce at a field site in Denmark to study the release of volatile compounds in response to a change in light. Whilst some compounds, like isoprene and sabinene, increased with increasing light, other compounds, like camphene, showed no light response for most of the trees. This can help to increase our knowledge of how species and compounds respond to light and to possibly improve how they can be modeled.

Nitrogen is the key nutrient that typically limits productivity in coastal waters. One of the key controls on the amount of bioavailable nitrogen is the process of denitrification, which converts nitrate (bioavailable) into nitrogen gas. Previous studies suggest high rates of denitrification may take place within carbonate sediments, and one explanation for this is that this process may take place within the sand grains. Here we show evidence to support this hypothesis.

Experiments that manipulate the temperature of plants and ecosystems are used to improve understanding of how they will respond to climate change. In logistically challenging locations passive warming using solar energy is the the only viable option for warming experiments. Unfortunately current passive warming approaches can only raise air temperature by about 1.5 °C. We have developed a novel approach that doubles the warming possible using solar energy and requires no power.

We provide direct and quantitative assessments showing the marine organic matter from eutrophication-induced primary production dominated oxygen consumption in the hypoxic zone, while the terrestrially sourced organic matter also significantly contributed to the formation and maintenance of hypoxia in the lower Pearl River Estuary (PRE) and the adjacent coastal water.

Water, Energy, and Carbon with Artificial Neural Networks (WECANN) is a statistically based estimate of global surface latent and sensible heat fluxes and gross primary productivity. The retrieval uses six remotely sensed observations as input, including the solar-induced fluorescence. WECANN provides estimates on a 1° × 1° geographic grid and on a monthly time scale and outperforms other global products in capturing the seasonality of the fluxes when compared to eddy covariance tower data.

We construct a model of the ocean's coupled phosphorus, silicon, and iron cycles and optimize its biogeochemical parameters. State estimates for widely differing iron sources are consistent with observations because of compensation between sources and sinks. Export production and the patterns of export supported by each iron source type (aeolian, sedimentary, hydrothermal) are well constrained. The fraction of export supported by each iron type varies systematically with its fractional source.

This study describes and evaluates a new ammonia (NH₃) exchange model for grazed fields (GAG_field). GAG_field is able to simulate the main features of the observed NH₃ fluxes. A sensitivity analysis for the non-meteorological model parameters showed that the sensitivity of the NH₃ fluxes to a parameter varies among urine patches. Moreover, the fluxes modelled with a dynamic soil pH are similar if a constant pH 7.5 is used, suggesting a useful simplification for regional-scale model application.

This study quantified, for the first time, simultaneous rates of carbon dioxide (CO₂) and nitrous oxide (N₂O) from a Mediterranean riparian forest. Our results showed a strong linkage between riparian hydrology, soil microbial processes, and greenhouse gas (GHG) emissions. High CO₂ effluxes occurred all year long, while N₂O emissions were generally low and confined to saturated soils. Overall, this study shows that riparian soils can be hotspots of GHG emissions within Mediterranean catchment.

We investigate the atmospheric sensitivity to an expansion in shrub and tree cover in the northern Fennoscandia region. We applied a regional weather and climate model in evaluating biophysical effects of increased shrub cover at a fine resolution. We find that shrub cover increase causes a warming that is sensitive to the shrub and tree heights. Cooling effects include increased snow cover, cloud cover, and precipitation. We show that the net warming will likely increase in the future.

The history of river inundation influences shoreline sediment biogeochemical cycling and microbial dynamics. Sediment exhibited a binary respiration response to rewetting, in which respiration from less recently saturated sediment was suppressed relative to more recently saturated sediment, likely due to inhibition of fungal metabolic activity. River shorelines should likely be integrated as a distinct environment into hydrobiogeochemical models to predict watershed biogeochemical function.

We investigate the likelihood of ecological in situ networks to detect and monitor the impact of extreme events in the terrestrial biosphere.

Permafrost soils store massive amounts of C, yet estimates of soil C storage in this region are highly uncertain, primarily due to undersampling at all spatial scales; circumpolar soil C estimates lack sufficient continental spatial diversity, regional intensity, and replication at the field-site level. We aim to reduce the uncertainty of regional C estimates by providing a comprehensive assessment of vegetation, active-layer, and permafrost C stocks in a watershed in northeast Siberia, Russia.

Calibration of terrestrial ecosystem models (TEMs) is important but challenging. This study applies an advanced sampling technique for parameter estimation of a TEM. The results improve the model fit and predictive performance.

We evaluate the Community Land Model (CLM4.5) against observations at an old-growth coniferous forest site that is subjected to water stress each summer. We found that, after calibration, CLM was able to reasonably simulate the observed fluxes of energy and carbon, carbon stocks, carbon isotope ratios, and ecosystem response to water stress. This study demonstrates that carbon isotopes can expose structural weaknesses in CLM and provide a key constraint that may guide future model development.

CO₂ loss from soil to the atmosphere (soil respiration) is a key ecosystem function, especially in systems with permafrost. We find that soil respiration shows a non-linear threshold at permafrost depths > 140 cm and that the number of large trees governs soil respiration. This suggests that remote sensing could be used to estimate spatial variation in soil respiration and (with knowledge of key thresholds) empirically constrain models that predict ecosystem responses to permafrost thaw.

El Niño–Southern Oscillation (ENSO) has been identified as one of the main drivers for the interannual variability in eastern African rainfall. But we know little about its direct impact on vegetation and how it might change in the future. In this study, we quantified this relationship and predict its future under certain climate change scenarios. Results suggest that we need to consider an increase in future ENSO intensity to cover the full range of potential changes in vegetation responses.

Permanent flooding of low-lying coastal areas is a growing threat due to climate-change-related sea-level rise. To reduce coastal damage, buffer zones can be created by managed coastal realignment where existing dykes are breached and new dykes are built further inland. We studied the impacts on organic matter degradation in soils flooded with seawater by managed coastal realignment and suggest that most of the organic carbon present in coastal soils will be permanently preserved after flooding.

Carbon and nutrient export regimes were analyzed from archetypal headwater catchments to downstream reaches. In headwater catchments, land use and lithology determine land-to-stream C, N and P transfer processes. The crucial role of riparian zones in C, N and P coupling was investigated. In downstream reaches, point-source contributions and in-stream processes alter C, N and P export regimes.

We investigated the response of water use efficiency (WUE) to summer drought in a boreal Scots pine forest (Pinus sylvestris) on the daily time scale mainly using EC flux data from the Hyytiälä (southern Finland) flux site. Simulation results from the JSBACH land surface model were also evaluated against the observed results. The performance of three WUE metrics at the ecosystem level (EWUE, IWUE, and uWUE) during the severe summer drought were studied and showed different results.