Permafrost Stores a Globally Significant Amount of Mercury

Schuster, Paul F.; Schaefer, Kevin; Aiken, George R.; Antweiler, Ronald C.; DeWild, John F.; Gryziec, Joshua D.; Gusmeroli, A.; Hugelius, Gustaf; Jafarov, Elchin; Krabbenhoft, David P.; Liu, Lin; Herman‐Mercer, Nicole M.; Mu, Cuicui; Roth, David A.; Schaefer, Tim; Striegl, Robert G.; Wickland, Kimberly P.

doi:10.1002/2017gl075571

Cited by 270 publications

(226 citation statements)

References 56 publications

Supporting

Mentioning

196

Contrasting

Order By: Relevance

“…Concerns regarding large tundra soil Hg pools are their potential mobilization induced by climate change (Schuster et al, 2018). While organic horizons showed Hg concentrations comparable to temperate soils, mineral horizon concentrations were 2-to-5 times higher than those observed in temperate areas and contained 75% of total Hg mass stored in tundra soil.…”

Section: Discussionmentioning

confidence: 86%

“…We compared results to a recent study by Schuster et al (2018), who measured Hg concentrations across 13 permafrost cores to depths of 166 cm, and reported Hg concentrations ranging from 17 to 207 μg/kg (mean of 64 μg/kg) in the permafrost zone and concentrations of 50 to 100 μg/kg in the active-layer zones. We compared results to a recent study by Schuster et al (2018), who measured Hg concentrations across 13 permafrost cores to depths of 166 cm, and reported Hg concentrations ranging from 17 to 207 μg/kg (mean of 64 μg/kg) in the permafrost zone and concentrations of 50 to 100 μg/kg in the active-layer zones.…”

Section: 1029/2017gb005840mentioning

confidence: 95%

“…Recently, Schuster et al (2018) studies support large magnitudes and role of Arctic soils as globally important storage pools for Hg. For example, the estimates for tundra soil active-layer Hg pools are very large compared to previous estimates of global soil Hg mass based on temperate studies (~240 Gg, Smith-Downey et al, 2010;~300 Gg, Hararuk et al, 2013;and 250 to 1,000 Gg with a best estimate of 500 Gg; Amos et al, 2015), and our estimate suggests that overall, global soil Hg pools may be greatly underestimated.…”

Section: Active-layer Hg Pool Sizes In Northern Alaska Arctic Tundra mentioning

confidence: 96%

“…Out of 478 soil data points found in the literature reporting Hg concentrations in Arctic tundra soils, concentrations ranged from 1 to 420 μg/kg with a median of 40 μg/kg and a mean of 57 μg/kg. Note that Schuster et al (2018) reported close correlations between soil organic C and soil Hg (for 80% of the data: r 2 of 0.98 for C content <10% and r 2 of 0.56 for >10%), so additional variance in scaling up Hg pools based on C inventories are due to imperfect Hg-to-C relationships). Soil Hg concentrations showed similar patterns in the upper 30 cm and lower 30-100 cm, both with median values of 40 μg/kg.…”

Section: Active-layer Hg Pool Sizes In Northern Alaska Arctic Tundra mentioning

confidence: 97%

See 3 more Smart Citations

Mercury in Active‐Layer Tundra Soils of Alaska: Concentrations, Pools, Origins, and Spatial Distribution

Olson

Jiskra

Biester

et al. 2018

Global Biogeochemical Cycles

View full text Add to dashboard Cite

Tundra soils serve as major sources of mercury (Hg) input to the Arctic Ocean via river runoff and coastal erosion; yet little information is available on tundra soil Hg concentrations, pool sizes, origins, and dynamics. We present a detailed investigation of Hg in the active layer (upper ~100 cm subject to seasonal thaw) of tundra soils across 11 sites in Alaska. Soil Hg concentrations in organic horizons (151 ± 7 μg/kg) were in the upper range of temperate soil organic horizons, and concentrations in mineral horizons (98 ± 6 μg/kg) were much higher than in temperate soils. Soil Hg concentrations declined from inland to coastal sites, in contrast to a hypothesized northward increase expected because of proximity to coastal atmospheric mercury depletion events. Principle component analyses and elemental ratios results show that exogenic sources dominated over geogenic sources—in A‐horizons (66 ± 4%) and mineral B‐horizons (51 ± 1%). 14C age‐dating suggested recent origins of Hg in surface soils but showed that mineral soils (more than 7,300 years old) must have accumulated atmospheric inputs across millennia leading to high soil concentrations and pools. We estimated a total Northern Hemisphere active‐layer tundra soil Hg pool of 184 Gg (range of 136 to 274 Gg), suggesting a globally important Hg storage pool. Tundra soils are subject to seasonal thaw and freeze dynamics, thereby providing large inputs to rivers, lakes, and the Arctic Ocean. Understanding processes that mobilize Hg from tundra soils will be critical to understanding future Arctic wildlife and human Hg exposures.

show abstract

Section: Discussionmentioning

confidence: 86%

Section: 1029/2017gb005840mentioning

confidence: 95%

Section: Active-layer Hg Pool Sizes In Northern Alaska Arctic Tundra mentioning

confidence: 96%

Section: Active-layer Hg Pool Sizes In Northern Alaska Arctic Tundra mentioning

confidence: 97%

See 2 more Smart Citations

Mercury in Active‐Layer Tundra Soils of Alaska: Concentrations, Pools, Origins, and Spatial Distribution

Olson

Jiskra

Biester

et al. 2018

Global Biogeochemical Cycles

View full text Add to dashboard Cite

show abstract

“…The high mobility of Hg implies that these deposits are transient even in the steady-state pre-human Hg cycle (Amos et al, 2013), and that they can be potentially mobilized by human impacts such as the thawing of Arctic permafrost (Schuster et al, 2018).…”

mentioning

confidence: 99%

A model of mercury cycling and isotopic fractionation in the ocean

Archer¹

2018

Preprint

View full text Add to dashboard Cite

Abstract. Mercury speciation and isotopic fractionation processes have been incorporated into the HAMOCC offline ocean tracer advection code. The model is fast enough to allow a wide exploration of the sensitivity of the Hg cycle in the oceans, and of human exposure to Hg via monomethyl-Hg incorporation into fish. Vertical particle transport of Hg appears to play a discernable role in setting present-day Hg distributions, which we surmise by the fact that in simulations without particle 10 transport, the high present-day Hg deposition rate leads to an Hg maximum at the sea surface, rather than a subsurface maximum as observed. Hg particle transport has only a relatively small impact on anthropogenic Hg uptake, but it sequesters Hg deeper in the water column, so that excess Hg is retained in the model ocean for longer after anthropogenic Hg deposition is stopped. The concentration of monomethyl Hg is sensitive to its production rate, with model experiments suggesting that human impacts on ocean oxygen concentrations could have as significant an impact on oceanic MMHg 15 concentration as the anthropogenic Hg emission itself. Eight different isotopic fractionation mechanisms are simulated, independently and combined together, to predict their expression in the spatial distributions of isotopic signatures of Hg species in the ocean.

show abstract

Screening‐level risk assessment of methylmercury for non‐anadromous Arctic char (Salvelinus alpinus)

Barst

Drevnick

Muir

et al. 2019

Enviro Toxic and Chemistry

View full text Add to dashboard Cite

Non‐anadromous forms of Arctic char (Salvelinus alpinus), those that are restricted to lakes and rivers, typically have higher mercury (Hg) concentrations than anadromous forms, which migrate to and from the sea. Using tissue burden data from the literature and our own analyses, we performed a screening‐level risk assessment of methylmercury (MeHg) for non‐anadromous Arctic char. Our assessment included 1569 fish distributed across 83 sites. Site‐specific mean total Hg concentrations in non‐anadromous Arctic char muscle varied considerably from 0.01 to 1.13 µg/g wet weight, with 21% (17 of 83 sites) meeting or exceeding a threshold‐effect level in fish of 0.33 µg/g wet weight, and 13% (11 of 83 sites) meeting or exceeding a threshold‐effect level in fish of 0.5 µg/g wet weight. Of the sites in exceedance of the 0.33‐µg/g threshold, 7 were located in Greenland and 10 in Canada (Labrador, Nunavut, and Yukon). All but one of these sites were located in interfrost or permafrost biomes. Maximum total Hg concentrations exceeded 0.33 µg/g wet weight at 53% of sites (40 of the 75 sites with available maximum Hg values), and exceeded 0.5 µg/g wet weight at 27% (20 of 75 sites). Collectively, these results indicate that certain populations of non‐anadromous Arctic char located mainly in interfrost and permafrost regions may be at risk for MeHg toxicity. This approach provides a simple statistical assessment of MeHg risk to non‐anadromous Arctic char, and does not indicate actual effects. We highlight the need for studies that evaluate the potential toxic effects of MeHg in non‐anadromous Arctic char, as well as those that aid in the development of a MeHg toxic‐effect threshold specific to this species of fish. Environ Toxicol Chem 2019;38:489–502. © 2018 SETAC

show abstract

Permafrost Stores a Globally Significant Amount of Mercury

Cited by 270 publications

References 56 publications

Mercury in Active‐Layer Tundra Soils of Alaska: Concentrations, Pools, Origins, and Spatial Distribution

Mercury in Active‐Layer Tundra Soils of Alaska: Concentrations, Pools, Origins, and Spatial Distribution

A model of mercury cycling and isotopic fractionation in the ocean

Screening‐level risk assessment of methylmercury for non‐anadromous Arctic char (Salvelinus alpinus)

Contact Info

Product

Resources

About