Siberian environmental change: Synthesis of recent studies and opportunities for networking

AMBIO, Journal Year: 2021, Volume and Issue: 50(11), P. 2104 - 2127

Published: Sept. 29, 2021

Language: Английский

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Tree line advance reduces mixing and oxygen concentrations in arctic–alpine lakes through wind sheltering and organic carbon supply

Global Change Biology, Journal Year: 2021, Volume and Issue: 27(18), P. 4238 - 4253

Published: May 8, 2021

Abstract Oxygen depletion in lake bottom waters has adverse impacts on ecosystem health including decreased water quality from release of nutrients and reduced substances sediments, the reduction fish growth reproduction. Depletion occurs when oxygen is consumed during decomposition organic matter, replenishment limited by column stratification. Arctic–alpine lakes are often well mixed oxygenated, but rapid climate change these regions an important driver shifts catchment vegetation that could affect mixing dynamics lakes. Here, we analyze high‐resolution time series dissolved concentration temperature profiles 40 Swedish arctic–alpine across tree line ecotone. The stratified for 1−125 days, stratification, near‐bottom concentrations changed −0.20 to +0.15 mg L −1 day , resulting final 1.1−15.5 at end longest stratification period. Structural equation modeling revealed with taller shoreline relative area had higher carbon consumption rates, also lower wind speeds longer periods, ultimately, concentrations. We use index canopy height predict variations among our study period ( R 2 = 0.41). Upscaling this relationship 8392 drop below 3, 5, 7 15%, 32%, 53% proportion sensitive (5%−22%, 13%−45%, 29%−69%) hypothetical observed past century or reconstructed Holocene (±200 m elevation; ±0.5° latitude). Assuming space‐for‐time substitution, advance will decrease many

Language: Английский

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Climate, not land-use, drives a recent acceleration of larch expansion at the forest-grassland ecotone in the southern French alps

The Science of The Total Environment, Journal Year: 2025, Volume and Issue: 959, P. 178326 - 178326

Published: Jan. 1, 2025

Language: Английский

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Trees First Inhibit Then Promote Litter Decomposition in the Subarctic

Ecology Letters, Journal Year: 2025, Volume and Issue: 28(1)

Published: Jan. 1, 2025

ABSTRACT Trees affect organic matter decomposition through allocation of recently fixed carbon belowground, but the magnitude and direction this effect may depend on substrate type stage. Here, we followed mass loss, chemical composition fungal colonisation leaf root litters incubated in mountain birch forests over 4 years, plots where belowground was severed by tree girdling or control plots. Initially, stimulated litter loss 12% 22%, respectively, suggesting competitive release saprotrophic when tree‐mediated competition ectomycorrhizal fungi eliminated (Gadgil effect). After instead hampered 30%, late‐stage priming presence trees, parallel with increased growth shrubs associated following elimination. Hence, different mechanisms driving early‐ should be considered climate‐feedback evaluations plant–soil interactions.

Language: Английский

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Spectroscopic Protocol for Biosignature Detection: Arctic Ice Samples as Analogs for Icy Moons

Astrobiology, Journal Year: 2025, Volume and Issue: unknown

Published: March 28, 2025

The moons of Jupiter and Saturn, such as Europa Enceladus, are strong candidates for the search life outside Earth. Together with use direct observational methods, physical chemical processes that take place on icy may be studied planetary field analogs, is, similar reachable locations Fieldwork performed analogs can test protocols technology applied future space missions to extraterrestrial environments. Arctic is a candidate studies. This study assesses spectroscopic protocol biosignature detection in Arctic, proxy moons. Samples ice water underneath were collected by our team different at nearby Hudson Bay, Canada, analysis detected presence humic acid all samples. On contrary, biosignatures amino acids β-carotene have been present concentrations below limit equipment used. With proper optimization, it will possible implement this simple relies lightweight

Language: Английский

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