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@PhDThesis{Sobral:2019:CaFlIs,
               author = "Sobral, Anahi Chimini",
                title = "Caracteriza{\c{c}}{\~a}o dos fluxos de isopreno nos biomas 
                         Amaz{\^o}nia, Cerrado e Pantanal",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2019",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2019-05-28",
             keywords = "Intera{\c{c}}{\~a}o biosfera-atmosfera, isopreno, biomas 
                         brasileiros, biosphere-atmosphere interaction, isoprene, brazilian 
                         biomes.",
             abstract = "No Brasil, a vegeta{\c{c}}{\~a}o natural da Amaz{\^o}nia, 
                         Cerrado e Pantanal t{\^e}m grande import{\^a}ncia quanto {\`a} 
                         emiss{\~a}o de compostos org{\^a}nicos vol{\'a}teis 
                         biog{\^e}nicos, principalmente o isopreno, com conhecimento 
                         abundante para a Amaz{\^o}nia, mas com informa{\c{c}}{\~o}es 
                         ainda pouco conhecidas para Cerrado e Pantanal, requerendo 
                         esfor{\c{c}}os para estimar as emiss{\~o}es de isopreno nessas 
                         {\'a}reas. Considerando essa car{\^e}ncia de 
                         informa{\c{c}}{\~a}o, esta tese investiga e descreve o 
                         comportamento das concentra{\c{c}}{\~o}es de isopreno em 
                         diferentes forma{\c{c}}{\~o}es vegetais brasileiras. Para tanto, 
                         foram realizadas incurs{\~o}es a campo na Amaz{\^o}nia e 
                         Pantanal, com coleta de amostras de ar para 
                         quantifica{\c{c}}{\~a}o da concentra{\c{c}}{\~a}o de isopreno 
                         e dados ambientais para cada bioma. A partir dos dados obtidos 
                         foram realizadas simula{\c{c}}{\~o}es das emiss{\~o}es de 
                         isopreno utilizando o modelo MEGAN, vers{\~a}o beta 2.1, 
                         al{\'e}m de um estudo explorando fluxos futuros de emiss{\~a}o 
                         de isopreno para as {\'a}reas de estudo. Ao estudar a raz{\~a}o 
                         de mistura do isopreno, foi poss{\'{\i}}vel identificar que a 
                         raz{\~a}o de mistura no Pantanal {\'e} menor que na 
                         Amaz{\^o}nia (9,19  4,73 ppb) durante a {\'e}poca seca. Isso 
                         foi atribu{\'{\i}}do n{\~a}o somente {\`a} import{\^a}ncia do 
                         tipo de vegeta{\c{c}}{\~a}o, mas tamb{\'e}m {\`a}s 
                         condi{\c{c}}{\~o}es ambientais locais, que podem ter 
                         influenciado os mecanismos de produ{\c{c}}{\~a}o do isopreno. No 
                         caso do Pantanal ainda foi identificada uma diferen{\c{c}}a 
                         estatisticamente significativa entre as campanhas realizadas em 
                         2016 (2,17  0,61 ppb) e 2017 (0.60  0,27 ppb), o que pode ter 
                         ocorrido devido ao impacto do grande n{\'u}mero de queimadas 
                         registradas em 2017. Ao comparar as emiss{\~o}es estimadas de 
                         isopreno nos tr{\^e}s biomas para o per{\'{\i}}odo analisado, a 
                         Amaz{\^o}nia desponta como o bioma cujo fluxo de isopreno {\'e} 
                         maior, seguido por Pantanal e Cerrado, tanto para as estimativas 
                         geradas pelo MEGAN (9,39, 4,08 e 2,50 mg m-2 h-1, 
                         respectivamente), quanto as derivadas pela coluna de 
                         formalde{\'{\i}}do (2,45, 1,66 e 0,69 mg m-2 h-1, 
                         respectivamente). Apesar de superestimar as emiss{\~o}es, o 
                         modelo MEGAN representou de maneira muito satisfat{\'o}ria a 
                         sazonalidade nos fluxos de isopreno para os biomas estudados. 
                         Quando se comparam as emiss{\~o}es m{\'e}dias anuais de isopreno 
                         estimadas pelo MEGAN em termos de contribui{\c{c}}{\~a}o por 
                         biomas, por conta da sua extens{\~a}o, o Pantanal apresenta a 
                         menor contribui{\c{c}}{\~a}o. Amaz{\^o}nia, Cerrado e Pantanal 
                         contribuem, respectivamente, com 334,15, 42,76 e 5,26 Tg isopreno 
                         ano-1. As simula{\c{c}}{\~o}es das emiss{\~o}es de isopreno 
                         frente a um poss{\'{\i}}vel cen{\'a}rio de mudan{\c{c}}a no 
                         clima tamb{\'e}m apontaram para uma redu{\c{c}}{\~a}o em 
                         aproximadamente 10 % nas emiss{\~o}es, j{\'a} que o aumento da 
                         concentra{\c{c}}{\~a}o do CO2 atmosf{\'e}rico exerce um efeito 
                         inibidor das emiss{\~o}es, sobrepondo-se ao est{\'{\i}}mulo 
                         fornecido pelo aumento da temperatura. ABSTRACT: In Brazil, the 
                         natural vegetation of the Amazon, Cerrado and Pantanal biomes 
                         presents great importance for the biogenic volatile organic 
                         compounds emission, mainly isoprene, with abundant knowledge for 
                         the Amazon, but with information not yet known for Cerrado and 
                         Pantanal, requiring efforts to estimate isoprene emissions in 
                         these areas. Considering this lack of information, this study 
                         investigates and describes the behavior of isoprene concentrations 
                         in different Brazilian biomes. For this purpose, field trips were 
                         carried out in the Amazon and Pantanal. In order to quantify the 
                         isoprene concentration, air samples were collected and the diurnal 
                         cycle of isoprene mixing ratio was analyzed in correlation to 
                         environmental parameters. Besides, in order to understand the 
                         isoprene emission behavior and magnitude for each biome, the MEGAN 
                         model, beta version 2.1, was used to simulate the emission. The 
                         MEGAN model was also used to explore future trends in isoprene 
                         emission for the study areas. By studying the isoprene mixing 
                         ratio of isoprene, it was possible to identify that the mixing 
                         ratio in the Pantanal is lower than in the Amazon (9,19  4,73 
                         ppb) during the dry season. This was attributed not only to the 
                         vegetation type, but also to local environmental conditions, which 
                         may have influenced the isoprene production mechanisms. In the 
                         case of Pantanal, a statistically significant difference between 
                         the campaigns carried out in 2016 (2,17  0,61 ppb) and 2017 (0,60 
                          0,27 ppb) was also identified, which may have occurred due to 
                         the impact of the large number of fires registered in 2017. When 
                         comparing the isoprene estimated emissions in the three biomes for 
                         the analyzed period, the Amazon emerges as the biome whose 
                         isoprene flux is higher, followed by Pantanal and Cerrado, both 
                         for the MEGAN (9.39, 4.08 and 2.50 mg m-2 h-1, respectively) and 
                         those derived from the formaldehyde column (2.45, 1.66 and 0.69 mg 
                         m-2 h-1, respectively). Despite MEGAN overestimated the isoprene 
                         flux, the model represented the flux seasonality very 
                         satisfactorily, for the analyzed period. When comparing the annual 
                         average isoprene emissions estimated by MEGAN in terms of biome 
                         contribution, Pantanal, due to its extension, presents the 
                         smallest contribution. Amazon, Cerrado and Pantanal contribute, 
                         respectively, with 334,15, 42,76 and 5,26 Tg isoprene year-1. The 
                         isoprene emission simulations in a possible climate change 
                         scenario shows a reduction of approximately 10 % in the emissions 
                         as a consequence of the atmospheric CO2 concentration increase, 
                         which has an inhibitory effect on emissions, overlapping the 
                         effect provided by the increase in temperature.",
            committee = "Forti, Maria Cristina (presidente) and Alval{\'a}, 
                         Pl{\'{\i}}nio Carlos (orientador) and von Randow, Celso 
                         (orientador) and Manzi, Antonio Ocimar and Pav{\~a}o, Hamilton 
                         Germano and Santos, Fernando Cavalcante",
         englishtitle = "Characterization of isoprene flux in the Amazon, Cerrado and 
                         Pantanal biomes",
             language = "pt",
                pages = "120",
                  ibi = "8JMKD3MGP3W34R/3T9JTTP",
                  url = "http://urlib.net/rep/8JMKD3MGP3W34R/3T9JTTP",
           targetfile = "publicacao.pdf",
        urlaccessdate = "27 nov. 2020"
}


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