Investigation of mercury emissions from burning of Australian eucalypt forest surface fuels using a combustion wind tunnel and field observations

Dean Howard, Katrina Macsween, Grant C. Edwards, Maximilien Desservettaz, Elise Andrée Guérette, Clare Paton-Walsh, Nicholas C. Surawski, Andrew L. Sullivan, Christopher Weston, Liubov Volkova, Jennifer Powell, Melita D. Keywood, Fabienne Reisen, C. P. (Mick) Meyer

Research output: Contribution to journalArticleResearchpeer-review

Abstract

Environmental cycling of the toxic metal mercury (Hg) is ubiquitous, and still not completely understood. Volatilisation and emission of mercury from vegetation, litter and soil during burning represents a significant return pathway for previously-deposited atmospheric mercury. Rates of such emission vary widely across ecosystems as they are dependent on species-specific uptake of atmospheric mercury as well as fire return frequencies. Wildfire burning in Australia is currently thought to contribute between 1 and 5% of the global total of mercury emissions, yet no modelling efforts to date have utilised local mercury emission factors (mass of emitted mercury per mass of dry fuel) or local mercury emission ratios (ratio of emitted mercury to another emitted species, typically carbon monoxide). Here we present laboratory and field investigations into mercury emission from burning of surface fuels in dry sclerophyll forests, native to the temperate south-eastern region of Australia. From laboratory data we found that fire behaviour — in particular combustion phase — has a large influence on mercury emission and hence emission ratios. Further, emission of mercury was predominantly in gaseous form with particulate-bound mercury representing <1% of total mercury emission. Importantly, emission factors and emission ratios with respect to carbon monoxide and carbon dioxide, from both laboratory and field data all show that gaseous mercury emission from biomass burning in Australian dry sclerophyll forests is currently overestimated by around 60%. Based on these results, we recommend a mercury emission factor of 28.7 ± 8.1 μg Hg kg −1 dry fuel, and emission ratio of gaseous elemental mercury relative to carbon monoxide of 0.58 ± 0.01 × 10 −7 , for estimation of mercury release from the combustion of Australian dry sclerophyll litter.

LanguageEnglish
Pages17-27
Number of pages11
JournalAtmospheric Environment
Volume202
DOIs
Publication statusPublished - 1 Apr 2019

Fingerprint

wind tunnel
wind field
combustion
carbon monoxide
mercury
dry forest
litter
fire behavior
biomass burning
volatilization
wildfire

Keywords

  • Australia
  • Biogeochemical cycling
  • Biomass burning
  • Emissions
  • gaseous elemental mercury

Cite this

Howard, Dean ; Macsween, Katrina ; Edwards, Grant C. ; Desservettaz, Maximilien ; Guérette, Elise Andrée ; Paton-Walsh, Clare ; Surawski, Nicholas C. ; Sullivan, Andrew L. ; Weston, Christopher ; Volkova, Liubov ; Powell, Jennifer ; Keywood, Melita D. ; Reisen, Fabienne ; (Mick) Meyer, C. P. / Investigation of mercury emissions from burning of Australian eucalypt forest surface fuels using a combustion wind tunnel and field observations. In: Atmospheric Environment. 2019 ; Vol. 202. pp. 17-27.
@article{6fe08b28b457417eb95a6f320dfee444,
title = "Investigation of mercury emissions from burning of Australian eucalypt forest surface fuels using a combustion wind tunnel and field observations",
abstract = "Environmental cycling of the toxic metal mercury (Hg) is ubiquitous, and still not completely understood. Volatilisation and emission of mercury from vegetation, litter and soil during burning represents a significant return pathway for previously-deposited atmospheric mercury. Rates of such emission vary widely across ecosystems as they are dependent on species-specific uptake of atmospheric mercury as well as fire return frequencies. Wildfire burning in Australia is currently thought to contribute between 1 and 5{\%} of the global total of mercury emissions, yet no modelling efforts to date have utilised local mercury emission factors (mass of emitted mercury per mass of dry fuel) or local mercury emission ratios (ratio of emitted mercury to another emitted species, typically carbon monoxide). Here we present laboratory and field investigations into mercury emission from burning of surface fuels in dry sclerophyll forests, native to the temperate south-eastern region of Australia. From laboratory data we found that fire behaviour — in particular combustion phase — has a large influence on mercury emission and hence emission ratios. Further, emission of mercury was predominantly in gaseous form with particulate-bound mercury representing <1{\%} of total mercury emission. Importantly, emission factors and emission ratios with respect to carbon monoxide and carbon dioxide, from both laboratory and field data all show that gaseous mercury emission from biomass burning in Australian dry sclerophyll forests is currently overestimated by around 60{\%}. Based on these results, we recommend a mercury emission factor of 28.7 ± 8.1 μg Hg kg −1 dry fuel, and emission ratio of gaseous elemental mercury relative to carbon monoxide of 0.58 ± 0.01 × 10 −7 , for estimation of mercury release from the combustion of Australian dry sclerophyll litter.",
keywords = "Australia, Biogeochemical cycling, Biomass burning, Emissions, gaseous elemental mercury",
author = "Dean Howard and Katrina Macsween and Edwards, {Grant C.} and Maximilien Desservettaz and Gu{\'e}rette, {Elise Andr{\'e}e} and Clare Paton-Walsh and Surawski, {Nicholas C.} and Sullivan, {Andrew L.} and Christopher Weston and Liubov Volkova and Jennifer Powell and Keywood, {Melita D.} and Fabienne Reisen and {(Mick) Meyer}, {C. P.}",
year = "2019",
month = "4",
day = "1",
doi = "10.1016/j.atmosenv.2018.12.015",
language = "English",
volume = "202",
pages = "17--27",
journal = "Atmospheric Environment",
issn = "1352-2310",
publisher = "Elsevier",

}

Howard, D, Macsween, K, Edwards, GC, Desservettaz, M, Guérette, EA, Paton-Walsh, C, Surawski, NC, Sullivan, AL, Weston, C, Volkova, L, Powell, J, Keywood, MD, Reisen, F & (Mick) Meyer, CP 2019, 'Investigation of mercury emissions from burning of Australian eucalypt forest surface fuels using a combustion wind tunnel and field observations', Atmospheric Environment, vol. 202, pp. 17-27. https://doi.org/10.1016/j.atmosenv.2018.12.015

Investigation of mercury emissions from burning of Australian eucalypt forest surface fuels using a combustion wind tunnel and field observations. / Howard, Dean; Macsween, Katrina; Edwards, Grant C.; Desservettaz, Maximilien; Guérette, Elise Andrée; Paton-Walsh, Clare; Surawski, Nicholas C.; Sullivan, Andrew L.; Weston, Christopher; Volkova, Liubov; Powell, Jennifer; Keywood, Melita D.; Reisen, Fabienne; (Mick) Meyer, C. P.

In: Atmospheric Environment, Vol. 202, 01.04.2019, p. 17-27.

Research output: Contribution to journalArticleResearchpeer-review

TY - JOUR

T1 - Investigation of mercury emissions from burning of Australian eucalypt forest surface fuels using a combustion wind tunnel and field observations

AU - Howard, Dean

AU - Macsween, Katrina

AU - Edwards, Grant C.

AU - Desservettaz, Maximilien

AU - Guérette, Elise Andrée

AU - Paton-Walsh, Clare

AU - Surawski, Nicholas C.

AU - Sullivan, Andrew L.

AU - Weston, Christopher

AU - Volkova, Liubov

AU - Powell, Jennifer

AU - Keywood, Melita D.

AU - Reisen, Fabienne

AU - (Mick) Meyer, C. P.

PY - 2019/4/1

Y1 - 2019/4/1

N2 - Environmental cycling of the toxic metal mercury (Hg) is ubiquitous, and still not completely understood. Volatilisation and emission of mercury from vegetation, litter and soil during burning represents a significant return pathway for previously-deposited atmospheric mercury. Rates of such emission vary widely across ecosystems as they are dependent on species-specific uptake of atmospheric mercury as well as fire return frequencies. Wildfire burning in Australia is currently thought to contribute between 1 and 5% of the global total of mercury emissions, yet no modelling efforts to date have utilised local mercury emission factors (mass of emitted mercury per mass of dry fuel) or local mercury emission ratios (ratio of emitted mercury to another emitted species, typically carbon monoxide). Here we present laboratory and field investigations into mercury emission from burning of surface fuels in dry sclerophyll forests, native to the temperate south-eastern region of Australia. From laboratory data we found that fire behaviour — in particular combustion phase — has a large influence on mercury emission and hence emission ratios. Further, emission of mercury was predominantly in gaseous form with particulate-bound mercury representing <1% of total mercury emission. Importantly, emission factors and emission ratios with respect to carbon monoxide and carbon dioxide, from both laboratory and field data all show that gaseous mercury emission from biomass burning in Australian dry sclerophyll forests is currently overestimated by around 60%. Based on these results, we recommend a mercury emission factor of 28.7 ± 8.1 μg Hg kg −1 dry fuel, and emission ratio of gaseous elemental mercury relative to carbon monoxide of 0.58 ± 0.01 × 10 −7 , for estimation of mercury release from the combustion of Australian dry sclerophyll litter.

AB - Environmental cycling of the toxic metal mercury (Hg) is ubiquitous, and still not completely understood. Volatilisation and emission of mercury from vegetation, litter and soil during burning represents a significant return pathway for previously-deposited atmospheric mercury. Rates of such emission vary widely across ecosystems as they are dependent on species-specific uptake of atmospheric mercury as well as fire return frequencies. Wildfire burning in Australia is currently thought to contribute between 1 and 5% of the global total of mercury emissions, yet no modelling efforts to date have utilised local mercury emission factors (mass of emitted mercury per mass of dry fuel) or local mercury emission ratios (ratio of emitted mercury to another emitted species, typically carbon monoxide). Here we present laboratory and field investigations into mercury emission from burning of surface fuels in dry sclerophyll forests, native to the temperate south-eastern region of Australia. From laboratory data we found that fire behaviour — in particular combustion phase — has a large influence on mercury emission and hence emission ratios. Further, emission of mercury was predominantly in gaseous form with particulate-bound mercury representing <1% of total mercury emission. Importantly, emission factors and emission ratios with respect to carbon monoxide and carbon dioxide, from both laboratory and field data all show that gaseous mercury emission from biomass burning in Australian dry sclerophyll forests is currently overestimated by around 60%. Based on these results, we recommend a mercury emission factor of 28.7 ± 8.1 μg Hg kg −1 dry fuel, and emission ratio of gaseous elemental mercury relative to carbon monoxide of 0.58 ± 0.01 × 10 −7 , for estimation of mercury release from the combustion of Australian dry sclerophyll litter.

KW - Australia

KW - Biogeochemical cycling

KW - Biomass burning

KW - Emissions

KW - gaseous elemental mercury

UR - http://www.scopus.com/inward/record.url?scp=85060114453&partnerID=8YFLogxK

U2 - 10.1016/j.atmosenv.2018.12.015

DO - 10.1016/j.atmosenv.2018.12.015

M3 - Article

VL - 202

SP - 17

EP - 27

JO - Atmospheric Environment

T2 - Atmospheric Environment

JF - Atmospheric Environment

SN - 1352-2310

ER -