Ghent University Academic Bibliography

Advanced

Biogeochemical factors affecting mercury methylation rate in two contaminated floodplain soils

T Frohne, J Rinklebe, U Langer, Gijs Du Laing UGent, S Mothes and R Wennrich (2012) BIOGEOSCIENCES. 9(1). p.493-507
abstract
An automated biogeochemical microcosm system allowing controlled variation of redox potential (EH) in soil suspensions was used to assess the effect of various factors on the mobility of mercury (Hg) as well as on the methylation of Hg in two contaminated floodplain soils with different Hg concentrations (approximately 5 mg Hg kg(-1) and > 30 mg Hg kg(-1)). The experiment was conducted under stepwise variation from reducing (approximately -350 mV at pH 5) to oxidizing conditions (approximately 600 mV at pH 5). Results of phospholipid fatty acids (PLFA) analysis indicate the occurrence of sulfate reducing bacteria (SRB) such as Desulfobacter species (10Me16:0, cy17:0, 10Me18:0, cy19:0) or Desulfovibrio species (18:2 omega 6,9), which are considered to promote Hg methylation. The products of the methylation process are lipophilic, highly toxic methyl mercury species such as the monomethyl mercury ion [MeHg+], which is named as MeHg here. The ln(MeHg/Hg-t) ratio is assumed to reflect the net production of monomethyl mercury normalized to total dissolved Hg (Hg-t) concentration. This ratio increases with rising dissolved organic carbon (DOC) to Hg-t ratio (ln(DOC/Hg-t) ratio) (R-2 = 0.39, p < 0.0001, n = 63) whereas the relation between ln(MeHg/Hg-t) ratio and lnDOC is weaker (R-2 = 0.09; p < 0.05; n = 63). In conclusion, the DOC/Hg-t ratio might be a more important factor for the Hg net methylation than DOC alone in the current study. Redox variations seem to affect the biogeochemical behavior of dissolved inorganic Hg species and MeHg indirectly through related changes in DOC, sulfur cycle, and microbial community structure whereas EH and pH values, as well as concentration of dissolved Fe3+/Fe2+ and Cl-seem to play subordinate roles in Hg mobilization and methylation under our experimental conditions
Please use this url to cite or link to this publication:
author
organization
year
type
journalArticle (original)
publication status
published
subject
keyword
SULFATE-REDUCING BACTERIA, FATTY-ACID PROFILES, ELBE RIVER GERMANY, ANOXIC ESTUARINE SEDIMENT, MICROBIAL COMMUNITIES, ORGANIC-MATTER, METHYLMERCURY PRODUCTION, AQUATIC ENVIRONMENT, HUMIC SUBSTANCES, LIPID PHOSPHATE
journal title
BIOGEOSCIENCES
Biogeosciences
volume
9
issue
1
pages
493 - 507
Web of Science type
Article
Web of Science id
000300229000033
JCR category
GEOSCIENCES, MULTIDISCIPLINARY
JCR impact factor
3.754 (2012)
JCR rank
13/170 (2012)
JCR quartile
1 (2012)
ISSN
1726-4170
DOI
10.5194/bg-9-493-2012
language
English
UGent publication?
yes
classification
A1
copyright statement
I have retained and own the full copyright for this publication
id
3239672
handle
http://hdl.handle.net/1854/LU-3239672
date created
2013-06-11 14:40:27
date last changed
2017-03-31 12:50:13
@article{3239672,
  abstract     = {An automated biogeochemical microcosm system allowing controlled variation of redox potential (EH) in soil suspensions was used to assess the effect of various factors on the mobility of mercury (Hg) as well as on the methylation of Hg in two contaminated floodplain soils with different Hg concentrations (approximately 5 mg Hg kg(-1) and {\textrangle} 30 mg Hg kg(-1)). The experiment was conducted under stepwise variation from reducing (approximately -350 mV at pH 5) to oxidizing conditions (approximately 600 mV at pH 5). Results of phospholipid fatty acids (PLFA) analysis indicate the occurrence of sulfate reducing bacteria (SRB) such as Desulfobacter species (10Me16:0, cy17:0, 10Me18:0, cy19:0) or Desulfovibrio species (18:2 omega 6,9), which are considered to promote Hg methylation. The products of the methylation process are lipophilic, highly toxic methyl mercury species such as the monomethyl mercury ion [MeHg+], which is named as MeHg here. The ln(MeHg/Hg-t) ratio is assumed to reflect the net production of monomethyl mercury normalized to total dissolved Hg (Hg-t) concentration. This ratio increases with rising dissolved organic carbon (DOC) to Hg-t ratio (ln(DOC/Hg-t) ratio) (R-2 = 0.39, p {\textlangle} 0.0001, n = 63) whereas the relation between ln(MeHg/Hg-t) ratio and lnDOC is weaker (R-2 = 0.09; p {\textlangle} 0.05; n = 63). In conclusion, the DOC/Hg-t ratio might be a more important factor for the Hg net methylation than DOC alone in the current study. Redox variations seem to affect the biogeochemical behavior of dissolved inorganic Hg species and MeHg indirectly through related changes in DOC, sulfur cycle, and microbial community structure whereas EH and pH values, as well as concentration of dissolved Fe3+/Fe2+ and Cl-seem to play subordinate roles in Hg mobilization and methylation under our experimental conditions},
  author       = {Frohne, T and Rinklebe, J and Langer, U and Du Laing, Gijs and Mothes, S and Wennrich, R},
  issn         = {1726-4170},
  journal      = {BIOGEOSCIENCES},
  keyword      = {SULFATE-REDUCING BACTERIA,FATTY-ACID PROFILES,ELBE RIVER GERMANY,ANOXIC ESTUARINE SEDIMENT,MICROBIAL COMMUNITIES,ORGANIC-MATTER,METHYLMERCURY PRODUCTION,AQUATIC ENVIRONMENT,HUMIC SUBSTANCES,LIPID PHOSPHATE},
  language     = {eng},
  number       = {1},
  pages        = {493--507},
  title        = {Biogeochemical factors affecting mercury methylation rate in two contaminated floodplain soils},
  url          = {http://dx.doi.org/10.5194/bg-9-493-2012},
  volume       = {9},
  year         = {2012},
}

Chicago
Frohne, T, J Rinklebe, U Langer, Gijs Du Laing, S Mothes, and R Wennrich. 2012. “Biogeochemical Factors Affecting Mercury Methylation Rate in Two Contaminated Floodplain Soils.” Biogeosciences 9 (1): 493–507.
APA
Frohne, T, Rinklebe, J., Langer, U., Du Laing, G., Mothes, S., & Wennrich, R. (2012). Biogeochemical factors affecting mercury methylation rate in two contaminated floodplain soils. BIOGEOSCIENCES, 9(1), 493–507.
Vancouver
1.
Frohne T, Rinklebe J, Langer U, Du Laing G, Mothes S, Wennrich R. Biogeochemical factors affecting mercury methylation rate in two contaminated floodplain soils. BIOGEOSCIENCES. 2012;9(1):493–507.
MLA
Frohne, T, J Rinklebe, U Langer, et al. “Biogeochemical Factors Affecting Mercury Methylation Rate in Two Contaminated Floodplain Soils.” BIOGEOSCIENCES 9.1 (2012): 493–507. Print.