Dynamic flux chamber measurement of gaseous mercury emission fluxes over soils. Part 1: simulation of gaseous mercury emissions from soils using a two-resistance exchange interface model

Environmental context Mercury is a neurotoxin that bioaccumulates in the aquatic food web. Atmospheric emissions from urban areas close to the coast could cause increased local mercury deposition to the ocean. Our study adds important new data to the current limited knowledge on atmospheric mercury emissions and dynamics in coastal urban areas. Abstract Approximately 50% of primary atmospheric mercury emissions are anthropogenic, resulting from e.g. emission hotspots in urban areas. Emissions from urban areas close to the coast are of interest because they could increase deposition loads to nearby coastal waters as well as contribute to long range transport of mercury. We present results from measurements of gaseous elemental mercury (GEM) and reactive gaseous mercury (RGM) in 15 coastal cities and their surrounding marine boundary layer (MBL). An increase of 15–90% in GEM concentration in coastal urban areas was observed compared with the remote MBL. Strong RGM enhancements were only found in two cities. In urban areas with statistically significant GEM/CO enhancement ratios, slopes between 0.0020 and 0.0087 ng m–3 ppb–1 were observed, which is consistent with other observations of anthropogenic enhancement. The emission ratios were used to estimate GEM emissions from the areas. A closer examination of data from Sydney (Australia), the coast of Chile, and Valparaiso region (Chile) in the southern hemisphere, is presented.

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Estimation of Gaseous Mercury Emissions in Germany: Inverse Modelling of Source Strengths at the Contaminated Industrial Site BSL Werk Schkopau

Mercury Contaminated Sites ◽

10.1007/978-3-662-03754-6_20 ◽

1999 ◽

pp. 377-392 ◽

Cited By ~ 2

Author(s):

O. Krüger ◽

R. Ebinghaus ◽

H. H. Kock ◽

I. Richter-Politz ◽

C. Geilhufe

Keyword(s):

Inverse Modelling ◽

Industrial Site ◽

Mercury Emissions ◽

Gaseous Mercury

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Effects of Brownfield Remediation on Total Gaseous Mercury Concentrations in an Urban Landscape

Sensors ◽

10.3390/s20020387 ◽

2020 ◽

Vol 20 (2) ◽

pp. 387

Author(s):

Linghui Meng ◽

Charles T. Driscoll ◽

Mario Montesdeoca ◽

Huiting Mao

Keyword(s):

Urban Areas ◽

Urban Landscape ◽

Urban Ecosystems ◽

Atmospheric Mercury ◽

Soil Restoration ◽

Total Gaseous Mercury ◽

Annual Average ◽

Mercury Emissions ◽

Gaseous Mercury ◽

Parking Lot

In order to obtain a better perspective of the impacts of brownfields on the land–atmosphere exchange of mercury in urban areas, total gaseous mercury (TGM) was measured at two heights (1.8 m and 42.7 m) prior to 2011–2012 and after 2015–2016 for the remediation of a brownfield and installation of a parking lot adjacent to the Syracuse Center of Excellence in Syracuse, NY, USA. Prior to brownfield remediation, the annual average TGM concentrations were 1.6 ± 0.6 and 1.4 ± 0.4 ng · m − 3 at the ground and upper heights, respectively. After brownfield remediation, the annual average TGM concentrations decreased by 32% and 22% at the ground and the upper height, respectively. Mercury soil flux measurements during summer after remediation showed net TGM deposition of 1.7 ng · m − 2 · day − 1 suggesting that the site transitioned from a mercury source to a net mercury sink. Measurements from the Atmospheric Mercury Network (AMNet) indicate that there was no regional decrease in TGM concentrations during the study period. This study demonstrates that evasion from mercury-contaminated soil significantly increased local TGM concentrations, which was subsequently mitigated after soil restoration. Considering the large number of brownfields, they may be an important source of mercury emissions source to local urban ecosystems and warrant future study at additional locations.

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Air/Surface Exchange of Gaseous Elemental Mercury at Different Landscapes in Mississippi, USA

Atmosphere ◽

10.3390/atmos10090538 ◽

2019 ◽

Vol 10 (9) ◽

pp. 538 ◽

Cited By ~ 3

Author(s):

James Cizdziel ◽

Yi Jiang ◽

Divya Nallamothu ◽

J. Brewer ◽

Zhiqiang Gao

Keyword(s):

Forest Floor ◽

Agricultural Soils ◽

Elemental Mercury ◽

Ecological Impacts ◽

Wetland Soil ◽

Flux Chamber ◽

Surface Exchange ◽

Gaseous Elemental Mercury ◽

Emission Fluxes ◽

Mesocosm Experiments

Mercury (Hg) is a global pollutant with human health and ecological impacts. Gas exchange between terrestrial surfaces and the atmosphere is an important route for Hg to enter and exit ecosystems. Here, we used a dynamic flux chamber to measure gaseous elemental Hg (GEM) exchange over different landscapes in Mississippi, including in situ measurements for a wetland (soil and water), forest floor, pond, mowed field and grass-covered lawn, as well as mesocosm experiments for three different agricultural soils. Fluxes were measured during both the summer and winter. Mean ambient levels of GEM ranged between 0.93–1.57 ng m−3. GEM emission fluxes varied diurnally with higher daytime fluxes, driven primarily by solar radiation, and lower and more stable nighttime fluxes, dependent mostly on temperature. GEM fluxes (ng m−2 h−1) were seasonally dependent with net emission during the summer (mean 2.15, range 0.32 to 4.92) and net deposition during the winter (−0.12, range −0.32 to 0.12). Total Hg concentrations in the soil ranged from 17.1 ng g−1 to 127 ng g−1 but were not a good predictor of GEM emissions. GEM flux and soil temperature were correlated over the forest floor, and the corresponding activation energy for Hg emission was ~31 kcal mol−1 using the Arrhenius equation. There were significant differences in GEM fluxes between the habitats with emissions for grass > wetland soil > mowed field > pond > wetland water ≈ forest ≈ agriculture soils. Overall, we demonstrate that these diverse landscapes serve as both sources and sinks for airborne Hg depending on the season and meteorological factors.

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Seasonal and Diurnal Variation of Air/Water Exchange of Gaseous Mercury in a Southern Reservoir Lake (Cane Creek Lake, Tennessee, USA)

Water ◽

10.3390/w12082102 ◽

2020 ◽

Vol 12 (8) ◽

pp. 2102

Author(s):

William C. Crocker ◽

Hong Zhang

Keyword(s):

Wind Speed ◽

Solar Radiation ◽

Water Exchange ◽

Meteorological Data ◽

Global Solar Radiation ◽

Primary Control ◽

Seasonal Trends ◽

Gaseous Mercury ◽

Air Temperatures ◽

Emission Fluxes

A year-long field study of mercury (Hg) air/water exchange was conducted at a southern reservoir lake, Cane Creek Lake (Cookeville, TN, USA). The Hg air/water exchange fluxes and meteorological data including solar radiation (global solar radiation, Rg and ultraviolent radiation, UVA), water and air temperatures, relative humidity, and wind speed were collected to study the daily and seasonal trends of the Hg air/water exchange at the lake in relation to solar radiation and wind speed. The Hg exchange fluxes generally exhibited diurnal patterns with a rise in the morning, a peak around noontime, and a fall in the afternoon through the evening, closely following the change of solar radiation. There were cases that deviated from this general daily trend. The Hg emission fluxes were all below 3 ng m−2 h−1 with the daily mean fluxes < 2 ng m−2 h−1. The fluxes in the summer (mean: 1.2 ng m−2 h−1) were higher than in the fall (mean: 0.6 ng m−2 h−1) and winter (mean: 0.7 ng m−2 h−1). The daily and seasonal trends of the Hg air/water exchange fluxes are similar to the trends of the changes of the dissolved gaseous mercury (DGM) concentrations in the lake observed in our previous study. Solar radiation was found to exert a primary control over the Hg air/water exchange, while wind speed appeared to have a secondary effect on the Hg exchange. The two-thin-film model was used to calculate Hg emission fluxes from the Cane Creek Lake water.

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