The Science of The Total Environment, Journal Year: 2024, Volume and Issue: 959, P. 178176 - 178176
Published: Dec. 20, 2024
Language: Английский
Journal of Molecular Structure, Journal Year: 2024, Volume and Issue: 1312, P. 138506 - 138506
Published: May 2, 2024
Language: Английский
Citations
5
Food Chemistry, Journal Year: 2024, Volume and Issue: 463, P. 141375 - 141375
Published: Sept. 20, 2024
Language: Английский
Citations
4
The Science of The Total Environment, Journal Year: 2025, Volume and Issue: 962, P. 178440 - 178440
Published: Jan. 1, 2025
Substantial amounts of mercury (Hg) are projected to be released into Arctic watersheds as permafrost thaws amid warmer and wetter conditions. This may have far-reaching consequences because the highly toxic methylated form Hg biomagnifies rapidly in ecosystems. However, understanding how climate change affects dynamics regions is limited due lack long-term records. Using a 27-ka sediment record from Burial Lake, northwestern Alaska, we examine well-characterized temperature, precipitation, vegetation shifts affected mobilization catchment underlain by permafrost. During Last Glacial Maximum (29.6-19.6 ka), concentrations (63 ± 5 μg/kg) flux (8.6 2.2 μg m-2 yr-1) remain relatively stable. Abrupt warming trends, starting at 17.6 ka, do not coincide with levels. After 15 ecosystem transitions shrub tundra, (101.2 peak 14.2 while (5.3 1.3 declines stabilizes. At ~11 increased precipitation coincides 72 % rise 32 increase compared average levels since ka. These results suggest that summer rainfall was primary driver catchment, shift influenced lake concentrations. 1990 CE, represent an 88 (196.3 sixfold (38.1 above background levels, underscoring need for further research understand driven anthropogenic emissions change.
Language: Английский
Citations
0
Scientific Reports, Journal Year: 2025, Volume and Issue: 15(1)
Published: Feb. 28, 2025
Permafrost soils are critical reservoirs for mercury (Hg), with the thawing process leading to release of this element into environment, posing significant environmental risks. Of particular concern is methylated form mercury, monomethylmercury (MMHg), known its adverse effects on Human health. Microbial communities play a pivotal role in formation MMHg by facilitating Hg methylation and demethylation MMHg, slowing crossing toxic threshold concentration environment. However, specific microbes involved still need be understood. This study aimed identify microbial drivers behind changes speciation (MMHg Hg) permafrost thaw lakes assess significance biotic component biogeochemistry. Sediment samples from two thermokarst Canadian sub-Arctic were collected during winter summer 2022. Gene-centric metagenomics using whole-genome sequencing (WGS) was employed key genes (hgcA hgcB) (merA merB), supported qPCR analyses. A seasonal decline diversity, methylation, hgcA gene coverage observed summer, mirroring patterns rates. Notably, sequences significantly more abundant than merAB sequences, contrasting trends. These results indicate shift community, transitioning dominance predominance summer. Environmental these dynamics integrated conceptual model. provide new insights processes influencing cycle Arctic undergoing degradation.
Language: Английский
Citations
0
Science Advances, Journal Year: 2025, Volume and Issue: 11(12)
Published: March 19, 2025
Mercury (Hg) is a global pollutant with substantial human health impacts. While most studies focus on atmospheric total Hg (THg) deposition, contributions of methylated (MeHg), including monomethylmercury (MMHg) and dimethylmercury (DMHg), remain poorly understood. To examine this, we use rain aerosol speciation data high-resolution surface DMHg measurements, collected transect from Alaskan coastal waters to the Bering Chukchi Seas. We observed significant fivefold increase in MeHg:THg fraction 10-fold for aerosols, closely linked elevated highest evasion (~9.4 picomoles per square meter hour) found upwelling near Aleutian Islands. These highlight previously underexplored aspect MeHg air-sea exchange its importance cycling concerns. Our findings emphasize by demonstrating that can be transported long distances (~1700 kilometers) Arctic, posing risks ecosystems.
Language: Английский
Citations
0
The Science of The Total Environment, Journal Year: 2025, Volume and Issue: 976, P. 179276 - 179276
Published: April 9, 2025
Organic matter sequestered in permafrost environments contains mercury (Hg) which can be exposed via thaw to conditions that favour its microbial conversion into organic and neurotoxic form, methylmercury (MeHg). Permafrost affects landscapes unevenly, creating a patchwork of controlled by ground ice distribution time since degradation. However, little is known about the relationship between evolution features net MeHg production thawing landscapes. Near Kangiqsualujjuaq, Nunavik (Québec), degradation mounds, such as lithalsas, creates evolving mosaics hydrological ecological with well-drained elevated surfaces, rim ridges, ponds where succession leads terrestrialisation. This research investigated whether geomorphic degrading lithalsa field, including revegetation ponds, environmental conducive methylation inorganic (IHg). Hydrological conditions, well total (THg), MeHg, percent carbon (C), nitrogen (N), sulfur (S), were assessed for 175 soil samples collected along chronosequence pond revegetation. The lithalsas increased Hg potential, %MeHg increasing from 0.57 % on intact mounds 4.6 thermokarst depressions. Among latter, highest values associated earliest phase evolution, newly submerged high activity reduced environment. decreased colonisation Cyperaceae (4.8 %) further terrestrialisation Sphagnum spp. (2.6 %), contain recalcitrant compounds may inhibit raising surface above water table. Air photo analysis reveals rapid progression towards complete disappearance field full ponds. In state, potential expected stabilise at levels comparable non-permafrost bogs.
Language: Английский
Citations
0
Journal of Hazardous Materials, Journal Year: 2025, Volume and Issue: 492, P. 138268 - 138268
Published: April 12, 2025
Language: Английский
Citations
0
Environmental Pollution, Journal Year: 2025, Volume and Issue: unknown, P. 126254 - 126254
Published: April 1, 2025
Language: Английский
Citations
0
Geochimica et Cosmochimica Acta, Journal Year: 2025, Volume and Issue: unknown
Published: May 1, 2025
Language: Английский
Citations
0
Progress In Oceanography, Journal Year: 2024, Volume and Issue: 222, P. 103224 - 103224
Published: Feb. 18, 2024
Despite the lack of local anthropogenic mercury sources, methylated (MeHg) concentrations in Arctic biota are higher than from lower latitudes. The main entry route occurs during bioconcentration seawater monomethylmercury (MMHg) into phytoplankton. known seasonal changes biological activity region, little is about cycling total (THg) and MeHg Ocean. Here, we report THg sampled northwestern Barents Sea water column late winter spring. In upper 500 m, significantly spring (0.64 ± 0.09 pmol L-1) compared to (0.53 0.07 L-1), driven by inputs surface waters atmospheric deposition dynamics changing sea ice conditions. Contrastingly, were (41 39 fmol (85 42 L-1). We suggest that most biotically demethylated both phytoplankton bacteria, with additional losses photodemethylation evasion. Our observations highlight importance demethylation potential uptake methylmercury coinciding bloom. Lastly, use our new data together previously published region construct a simplified cycle an marginal zone.
Language: Английский
Citations
3