title: A simple approach for measuring emission patterns of vapor phase mercury under temperature-controlled conditions from soil.
abstract: In an effort to study the possible effects of climate change on the behavior of atmospheric mercury (Hg), we built a temperature-controlled microchamber system to measure its emission from top soils. To this end, mercury vapour emission rates were investigated in the laboratory using top soil samples collected from an urban area. The emissions of Hg, when measured as a function of soil temperature (from ambient levels up to 70°C at increments of 10°C), showed a positive correlation with rising temperature. According to the continuous analyses of the Hg vapor given off by the identical soil samples, evasion rate diminished noticeably with increasing number of repetitions. The experimental results, if examined in terms of activation energy (Ea), showed highly contrasting patterns between the single and repetitive runs. Although the results of the former exhibited Ea values smaller than the vaporization energy of Hg (i.e., <14 Kcal mol(-1)), those of the latter increased systematically with increasing number of repetitions. As such, it is proposed that changes in the magnitude of Ea values can be used as a highly sensitive criterion to discriminate the important role of vaporization from other diverse (biotic/abiotic) processes occurring in the soil layer.
authors.affiliation: Department of Environment and Energy, Sejong University, Seoul, Republic of Korea. khkim@sejong.ac.kr
authors.forename: Ki-Hyun
authors.initials: KH
authors.lastname: Kim
authors.forename: Hye-On
authors.initials: HO
authors.lastname: Yoon
authors.forename: Myung-Chae
authors.initials: MC
authors.lastname: Jung
authors.forename: Jong-Min
authors.initials: JM
authors.lastname: Oh
authors.forename: Richard J C
authors.initials: RJ
authors.lastname: Brown
mesh_terms: D000393:Air Pollutants / Q000032:analysis* / Q000737:chemistry; D004784:Environmental Monitoring / Q000295:instrumentation / Q000379:methods*; D005740:Gases / Q000032:analysis / Q000737:chemistry; D008628:Mercury / Q000032:analysis* / Q000737:chemistry; D012680:Sensitivity and Specificity; D012987:Soil / Q000032:analysis* / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis / Q000737:chemistry; D013696:Temperature; D014835:Volatilization
chemical_list: D000393:Air Pollutants; D005740:Gases; D012987:Soil; D012989:Soil Pollutants; D008628:Mercury