Several recent studies have indicated that forest fires are likely to re‐emit important quantities of atmospherically deposited mercury (Hg) to the atmosphere. Although the Amazon forest accounts for approximately 25% of the world's total rainforest, few data are available about these emissions. The emissions of mercury from prescribed fires of two 4‐ha plots of Amazon forest were investigated. Hg concentration and Hg burden were determined for vegetation, litter and soil before and after the fires. The data show that only Hg present in the aboveground vegetation and in the O‐horizon was volatilised; no significant soil emission was observed. Before the fire, the Hg stored in the vegetation (logs, branches, leaves and litter) ranged from 3.7 to 4.0 g ha−1 while 1.8 g ha−1 was found in the O‐horizon. The mass balance calculations of the present work indicate an average Hg emission of 3.5 g ha−1 due to forest fires, with 1.6 ha−1 originating from O‐horizon and 1.9 from above ground vegetation. On the base of the average annual deforestation rate of the Brazilian Amazon between 2000 and 2008, an annual Hg emission of 6.7 Mg yr−1 was estimated.

As concentrações de Mercúrio Gasoso Total (MGT) e Mercúrio Particulado Total (MPT) foram monitoradas durante as estações seca e úmida de 2002-2003 em dois pontos (industrial e residencial) da Região Metropolitana de Campinas. Não foi observada diferença significativa entre as concentrações dos pontos de amostragem e as concentrações médias foram 7,0 ± 5,8 ng m -3 (MGT) e 0,4 ± 0,3 ng m -3 (MPT). A análise da variação nictemeral mostrou maior concentração de MGT durante o dia, que poderia estar relacionada com maior atividade antrópica durante o dia. Processos de dispersão atmosférica também poderiam explicar algumas variações sazonais observadas na concentração de MGT. Para o MPT foi observada uma tendência de diminuição da concentração durante a estação úmida, o que poderia ser explicado pela remoção das partículas por deposição úmida. As concentrações de MGT e MPT encontradas neste estudo são da mesma ordem de magnitude das encontradas em regiões industrializadas do hemisfério norte. Estes resultados mostram que as emissões das regiões mais industrializadas do Brasil, e provavelmente de vários outros pais do hemisfério sul, deveriam também ser inventariadas e levadas em conta nos cálculos das emissões globais de mercúrio de origem antrópica. The concentrations of Total Gaseous Mercury (TGM) and Total Particulate Mercury (TPM)were monitored during the 2002-2003 rainy and dry seasons at two sampling points (industrial and residential areas) of the Campinas Metropolitan Region. No significant difference was observed between the concentrations found at the two sampling areas and the mean values were 7.0 ± 5.8 ng m -3 (TGM) and 0.4 ± 0.3 ng m -3 (TPM). The analysis of the diel variability showed higher TGM concentrations during the day, which could be related to more intense anthropogenic activity during the day. Atmospheric dispersion processes could also explain some seasonal variation observed in TGM concentrations. For TPM concentrations a decreasing trend was observed during the rainy season, which could be explained by the removal of particles by wet deposition. The concentrations of TGM and TPM found in this study were of the same order of magnitude of those recorded in some highly industrialized regions of the northern hemisphere. These data show that emissions from the most industrialized Brazilian regions, and probably from similar regions in other countries of the southern hemisphere, should also be assessed and integrated into the global anthropogenic mercury emission assessment.

A Deus por me guiar e proteger em todos os momentos da minha vida À Anne pela confiança e orientação a cada passo do caminho.Ao Ricardo e à Renata pelo amor, compreensão e alegria que tornaram leves os dias difíceis.A minha mãe Regina, sempre presente em todos os momentos, pelo carinho, compreensão e incentivo que nunca faltaram.Ao meu pai Paulo e aos meus irmãos Daniel, Lucas e Matias pelo apoio, incentivo e dedicação sempre.À Maria do Socorro pela amizade e companheirismo. À Gabriella, Eduardo, Larissa e Jonas, pela amizade e apoio em todos os momentos.

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