Soil and biomass mercury emissions during a prescribed fire in the Amazonian rain forest Jose J. Melendez-Perez a , Anne H. Fostier a, * , Jo ~ ao A. Carvalho Jr. b , Claudia C. Windm € oller c , Jos  e C. Santos d , Anthony Carpi e a Institute of Chemistry, University of Campinas, UNICAMP, P.O. Box 6154,13083-970 Campinas, SP, Brazil b S~ ao Paulo State University, UNESP, Av. Ariberto Pereira da Cunha 333,12516-410 Guaratinguet a, SP, Brazil c Department of Chemistry, Minas Gerais Federal University, UFMG, P.O. Box 702, 31270-901 Belo Horizonte, MG, Brazil d National Space Research Institute, INPE, Rodovia Presidente Dutra Km 40, 12630-000 Cachoeira Paulista, SP, Brazil e John Jay College, CUNY, Department of Sciences, 445 W 59th St, New York, NY 10019, USA highlights graphical abstract  4.1 ± 1.4 g mercury ha 1 were released from a prescribed fire in the Amazon basin.  Litterfall and the soil O-horizon accounted for 78% of released Hg.  Wood accounted for the smallest contribution emitted mercury.  Gaseous mercury continued to be released from soil following the burn event. article info Article history: Received 18 November 2013 Received in revised form 14 June 2014 Accepted 16 June 2014 Available online 21 June 2014 Keywords: Forest fire Mercury emissions Amazon abstract Mercury stored in forests can be volatilized to the atmosphere during fires. Many factors influence this process such as mercury concentration, vegetation loading and the soil temperature reached during the fire. We quantified mercury emissions from biomass and soil during a prescribed fire in Brazil using the difference in mercury burden in vegetation and soil before and after burning, and data were critically compared with those previously obtained in a similar experiment in another part of the Amazonia. The calculated mercury emission factor was 4.1 ± 1.4 g Hg ha 1 , with the main part (78%) originating from litterfall and O-horizon, and only 14% associated with live biomass. When considering the fuel burned loading, the emission factor ranged from 40 to 53 mg Hg kg 1 . Data were also obtained on soil tem- perature profile and on Hg speciation in soil in an effort to relate these parameters to Hg emissions. © 2014 Elsevier Ltd. All rights reserved. 1. Introduction Forest canopies are effective in trapping atmospheric mercury (Hg) because they present a large adsorption and assimilation surface area for particulate and gaseous mercury (Fay and Gustin, 2007; Frescholtz et al., 2003). Mercury compounds that accumu- late on foliage are then transferred to the soil by foliage wash off (by rainfall) and by litterfall deposition (Rea et al., 2002). In this manner, forest ecosystems act as an Hg sink, limiting the mobility of * Corresponding author. E-mail addresses: magojmp@hotmail.com (J.J. Melendez-Perez), fostier@iqm. unicamp.br (A.H. Fostier), joao@feg.unesp.br (J.A. Carvalho), claudiaufmg@ hotmail.com (C.C. Windm€ oller), jcarlos@lcp.inpe.br (J.C. Santos), acarpi@jjay.cuny. edu (A. Carpi). Contents lists available at ScienceDirect Atmospheric Environment journal homepage: www.elsevier.com/locate/atmosenv http://dx.doi.org/10.1016/j.atmosenv.2014.06.032 1352-2310/© 2014 Elsevier Ltd. All rights reserved. Atmospheric Environment 96 (2014) 415e422