Nitrous oxide (N₂O) and methane (CH₄) are atmospheric trace gases which play important roles in the climate and atmospheric chemistry of the Earth. However, little is known about their emissions from rivers and estuaries. To this end, concentrations of N₂O and CH₄ were measured during a seasonal study in six rivers and estuaries in northwestern Borneo. The concentrations of both gases were mainly driven by rainfall. The rivers and estuaries were an overall net source of atmospheric N₂O and CH₄.

Along the Namibian and Angolan margins, low oxygen conditions do not meet environmental ranges for cold–water corals and hence are expected to be unsuitable habitats. Environmental conditions show that tidal movements deliver water with more oxygen and high–quality organic matter, suggesting that corals compensate unfavorable conditions with availability of food. With the expected expansion of oxygen minimum zones in the future, this study provides an example how ecosystems cope with extremes.

Using field data collected over 4 years across a range of stand ages, we investigated how seasonal surface albedo in boreal forest varies with stand age, stand structure, and composition. Our results indicate that successional change in species composition is a key driver of age–related patterns in albedo, with hardwood species associated with higher albedo. The patterns described have important implications for both climate modeling and climate–smart boreal forest management.

Here we report that abrupt increases in temperature–simulating marine heatwaves might have the potential to shape the physiological state and biogenic sulfur production in microalgae involved in harmful algal blooms. Changes in physiology and biochemistry seem to trigger a shift in the bacteria community associated with these microalgae. Since microalgae and associated bacteria play an important role in climate regulation, this could have serious consequences for our future ocean and climate.

In this study, we examine the responses of E. huxleyi to a future warmer and more thermally variable ocean. Elevated temperatures and thermal variation have negative effects on growth rate and physiology that are especially pronounced at high temperatures, but high-frequency thermal variation may reduce the risk of extreme high-temperature events. These findings have potentially large implications for ocean productivity and marine biogeochemical cycles under a future changing climate.

We report on direct measurements of net ecosystem productivity (NEP) and net ecosystem calcification (NEC) in a Florida Bay seagrass ecosystem. We found notable differences between our carbon-based NEP and similar determinations made using oxygen. Over the study period, both NEP and NEC were negative, revealing that these sites are net heterotrophic and have dissolved CaCO₃. Our findings point to sediments maintaining negative NEP and NEC despite high seagrass above-ground primary production.

The release of elements from soil through weathering is an important process, controlling nutrient availability for plants and recovery from acidification. However, direct measurements cannot be done, and present estimates are burdened with high uncertainties. In this paper we use different approaches to quantify weathering rates in different scales in Sweden and discuss the pros and cons. The study contributes to more robust assessments of sustainable harvesting of forest biomass.

Carbon dioxide concentrations (pCO₂) in the atmosphere play an integral role in Earth system dynamics, especially climate. Past climates help us understand future ones, but reconstructing pCO₂ over the geologic record remains a challenge. This research demonstrates new approaches for exploring past pCO₂ via the carbon isotope fractionation in general algal lipids, which we test over a high CO₂ gradient from a naturally occurring CO₂ seep.

Across the Amazon rainforest, trees take in carbon through photosynthesis. However, photosynthesis across the basin is threatened by predicted shifts in rainfall patterns. To unpick how changes in rainfall affect photosynthesis, we use a model which combines climate data with our knowledge of photosynthesis and other plant processes. We find that stomatal constraints are less important, and instead shifts in leaf surface area and leaf properties drive changes in photosynthesis with rainfall.

Nitric oxide (NO) seems to be widespread, with different functions in the marine ecosystem, but we know little about it. Concentrations of NO were in a range from below the limit of detection to 616 pmol L⁻¹ at the surface and 482 pmol L⁻¹ at the bottom of the Bohai and Yellow seas. The study region was a source of atmospheric NO. Net NO sea-to-air fluxes were much lower than NO photoproduction rates, implying that the NO produced in the mixed layer was rapidly consumed before entering the air.

Increased dissolved organic carbon (DOC) concentration in streams can pose a threat to downstream water resources. Analyzing data from an in-stream probe we found that hydroclimatic and hydrological drivers can describe up to 72 % of the observed DOC concentration and composition variability. Variability was found to be highest during discharge events with warm and dry preconditions. The findings suggest an impact of climate change on DOC exports and thus also on downstream water quality.

Our understanding of terrestrial organic matter (TOM) in tropical peat-draining rivers remains limited, especially in Southeast Asia. We explored the characteristics of TOM via bulk parameters and lignin phenols of sediment in Malaysia. This showed that the most important plant source of the organic matter in these rivers is woody angiosperm C₃ plants with limited diagenetic alteration. This slower degradation of TOM may be a link to higher total nitrogen content, especially for the small river.