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@PhDThesis{Muler:2018:AnReSa,
               author = "Muler, Ranieli dos Anjos de Souza",
                title = "An{\'a}lise da resposta sazonal e interanual da din{\^a}mica 
                         florestal utilizando dados do sensor MODIS/MAIAC e medidas in situ 
                         em um fragmento de floresta no Sudoeste da Amaz{\^o}nia",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2018",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2018-08-10",
             keywords = "ecofisiologia, secas sazonais e extremas, fenologia, 
                         Amaz{\^o}nia, sensoriamento remoto, ecophysiology, seasonal and 
                         extreme droughts, phenology, Amazon, remote sensing.",
             abstract = "Florestas tropicais t{\^e}m um importante papel no ciclo e 
                         estoque de carbono, e na regula{\c{c}}{\~a}o do clima. Nas 
                         {\'u}ltimas d{\'e}cadas, severos eventos de seca foram 
                         registrados sobre as florestas tropicais amaz{\^o}nicas, a 
                         exemplo das secas de 2005, 2010 e 2015/16. Os modelos 
                         clim{\'a}ticos t{\^e}m previsto que estes eventos ser{\~a}o 
                         mais frequentes nos pr{\'o}ximos anos e reportado, ainda, um 
                         aumento na temperatura. Durante per{\'{\i}}odos de seca, sazonal 
                         ou interanual, tem sido observado diferentes respostas da floresta 
                         amaz{\^o}nica em termos de capacidade fotossint{\'e}tica do 
                         dossel, {\'a}rea foliar, crescimento de madeira e mortalidade. 
                         Mas, a din{\^a}mica sazonal da floresta n{\~a}o {\'e} 
                         impulsionada apenas pela disponibilidade de {\'a}gua, uma vez que 
                         s{\'{\i}}tios de estudo n{\~a}o limitados por {\'a}gua 
                         t{\^e}m mostrado aumento da capacidade fotossint{\'e}tica 
                         durante a esta{\c{c}}{\~a}o seca, impulsionado pelo aumento de 
                         radia{\c{c}}{\~a}o. As quest{\~o}es que envolvem a 
                         din{\^a}mica da floresta amaz{\^o}nica sob condi{\c{c}}{\~o}es 
                         de altera{\c{c}}{\~o}es nos recursos ambientais 
                         dispon{\'{\i}}veis, ainda s{\~a}o objeto de debate. Diante 
                         disso, o presente trabalho teve por objetivo avaliar a resposta 
                         sazonal e interanual de um fragmento de floresta de terra firme no 
                         Sudoeste da Amaz{\^o}nia {\`a} seca, por meio de dados de 
                         sensoriamento remoto (SR) e medidas in situ. A {\'a}rea de estudo 
                         compreende uma parcela de 5 ha localizada no s{\'{\i}}tio RJA, 
                         estado de Rond{\^o}nia, que foi monitorada entre 2015/17. 
                         Inicialmente foram avaliados os aspectos climatol{\'o}gicos do 
                         s{\'{\i}}tio de estudo, e a intensidade do extremo de seca 
                         atrav{\'e}s do {\'{\i}}ndice Standard precipitation index 
                         (SPI). Em seguida, a resposta da floresta foi avaliada sob quatro 
                         pontos de vista: i) resposta fenol{\'o}gica do dossel, tomando 
                         como base a varia{\c{c}}{\~a}o do {\'{\i}}ndice de 
                         vegeta{\c{c}}{\~a}o Enhanced vegetation index (EVI) e do Green 
                         chromatic coordinate (Gcc) como proxy da capacidade 
                         fotossint{\'e}tica e produ{\c{c}}{\~a}o de folhas novas, 
                         derivados do sensor Moderate Resolution Imaging Spectroradiometer 
                         (MODIS), com efeitos de nuvens, aeross{\'o}is e artefatos da 
                         geometria sensor-sol corrigidos pelo algoritmo Multi- Angle 
                         Implementation of Atmospheric Correction (MAIAC), ii) resposta 
                         fisiol{\'o}gica, com uso de medidas de crescimento do tronco, 
                         obtidas com dendr{\^o}metros pontuais e, produ{\c{c}}{\~a}o de 
                         serapilheira iii) resposta ecofisiol{\'o}gica, com uso de 
                         atributos funcionais indicativos de toler{\^a}ncia {\`a} seca 
                         (potencial em que a planta perde 50% da condutividade 
                         hidr{\'a}ulica (P50), potencial no ponto de perda de turgor 
                         (\πTLP) e isohidricidade) e iv) propriedades 
                         f{\'{\i}}sicas e qu{\'{\i}}micas do solo, al{\'e}m de umidade 
                         do solo e profundidade do len{\c{c}}ol fre{\'a}tico. Os 
                         resultados n{\~a}o demonstraram comportamento padronizado da 
                         floresta em rela{\c{c}}{\~a}o {\`a}s varia{\c{c}}{\~o}es 
                         interanuais do clima. Durante o evento de El-Niņo de 2015/16 
                         instaurou-se um epis{\'o}dio de seca de grau leve no 
                         s{\'{\i}}tio de estudo entre novembro de 2015 e maio de 2016, 
                         nesse per{\'{\i}}odo, foi observada uma redu{\c{c}}{\~a}o de 
                         ~7% na precipita{\c{c}}{\~a}o e aumento m{\'e}dio de ~1°C na 
                         temperatura do ar. Na an{\'a}lise em n{\'{\i}}vel de dossel, 
                         uma diminui{\c{c}}{\~a}o do EVI (efeito browning) foi observada 
                         durante a esta{\c{c}}{\~a}o seca, com respectivo aumento (efeito 
                         greenning) ocorrendo na esta{\c{c}}{\~a}o chuvosa. O EVI foi um 
                         melhor indicativo da maturidade foliar, devido apresentar aumento 
                         entre tr{\^e}s a cinco meses ap{\'o}s o pico de 
                         produ{\c{c}}{\~a}o de folhas novas visto com o Gcc. Os atributos 
                         funcionais P50, \πTLP e o predominante comportamento 
                         anisoh{\'{\i}}drico (baixa regula{\c{c}}{\~a}o 
                         estom{\'a}tica) das esp{\'e}cies arb{\'o}reas monitoradas, 
                         indicaram que a floresta apresenta grau moderado de 
                         resist{\^e}ncia {\`a} seca no contexto da parcela de estudo, 
                         considerando todas as classes de di{\^a}metro. O crescimento 
                         m{\'e}dio anual das {\'a}rvores foi de 0,18 ą 0,15 cm.ano-1, com 
                         menores valores durante a esta{\c{c}}{\~a}o seca, e menor 
                         incremento entre as esp{\'e}cies de di{\^a}metro < 20 cm. Os 
                         atributos funcionais demonstraram que as {\'a}rvores mais finas 
                         s{\~a}o, tamb{\'e}m, menos resistentes {\`a} seca. A {\'a}gua 
                         foi o principal fator limitante para a din{\^a}mica xii da 
                         floresta em n{\'{\i}}vel de dossel, uma vez que, o EVI (Rē=0,37) 
                         e a serapilheira total (Rē=0,56), apresentaram 
                         correla{\c{c}}{\~a}o significativa com a 
                         precipita{\c{c}}{\~a}o (\α=0,05), e tamb{\'e}m em 
                         n{\'{\i}}vel fisiol{\'o}gico devido a correla{\c{c}}{\~a}o 
                         significativa entre crescimento das {\'a}rvores e a 
                         precipita{\c{c}}{\~a}o (Rē=0,19) e umidade do solo (Rē=0,24) 
                         (\α=0,05). Durante a ocorr{\^e}ncia do epis{\'o}dio de 
                         El-Niņo em 2015/16, foram observados \ΔEVI e \ΔGcc 
                         negativos. Mas, efeitos no crescimento foram vistos p{\'o}s 
                         El-Niņo, sugerindo que a frequ{\^e}ncia de anomalias negativas na 
                         precipita{\c{c}}{\~a}o possa ser cr{\'{\i}}tica para a 
                         floresta, independente da intensidade da seca. ABSTRACT: Tropical 
                         forests play an important role in carbon cycle and stock, and in 
                         climate regulation. In recent decades, severe drought events have 
                         been recorded on the Amazon rainforest, as in the case of the 
                         2005, 2010 and 2015/16 droughts. The climate models have predicted 
                         that these events will be more frequent in the coming years and 
                         also reported an increase in temperature. During periods of 
                         drought, seasonal or interannual, different responses of the 
                         Amazon forest in terms of photosynthetic capacity of the canopy, 
                         leaf area, wood growth and mortality have been observed. However, 
                         the seasonal dynamics of the forest is not only driven by the 
                         availability of water, since study sites not limited by water have 
                         shown increased photosynthetic capacity during the dry season, 
                         driven by increased radiation. The issues surrounding the dynamics 
                         of the Amazon forest under conditions of changes in available 
                         environmental resources are still under discussion. The objective 
                         of this study was to evaluate the seasonal and interannual 
                         response of a dryland forest fragment in the Southwest of the 
                         Amazon to drought, using remote sensing (SR) data and in situ 
                         measurements. The study area comprises a plot of 5 ha located on 
                         the RJA site, state of Rond{\^o}nia, which was monitored between 
                         2015/17. The climatological aspects of the study site were 
                         evaluated, and the intensity of the drought were measured through 
                         the Standard Precipitation Index (SPI). Then the forest response 
                         was evaluated from four points of view: i) the canopy phenological 
                         response, based on the variation of the vegetation index Enhanced 
                         vegetation index (EVI) and the Green chromatic coordinate (Gcc) as 
                         a proxy for the photosynthetic capacity and the production of new 
                         leaves, derived from the Moderate Resolution Imaging 
                         Spectroradiometer (MODIS) sensor, with effects of clouds, aerosols 
                         and sensor-sol geometry corrected by the Multi-Angle 
                         Implementation of Atmospheric Correction (MAIAC) algorithm; ii) 
                         physiological response, using trunk growth measurements, obtained 
                         with point dendrometers and litterfall (iii) ecophysiological 
                         response, using functional attributes indicative of drought 
                         tolerance (water potential in which the plant loses 50% of the 
                         hydraulic conductivity (P50), water potential at the turgor loss 
                         point (\πTLP) and isohydricity) and iv) physical and 
                         chemical properties of the soil, as well as soil moisture and 
                         water table. The results did not demonstrate standardized forest 
                         behavior in relation to interannual climate variations. During the 
                         El-Niņo event of 2015/16, a mild-grade drought episode was 
                         established at the study site between November 2015 and May 2016, 
                         during which a reduction of ~7% in precipitation and a mean 
                         increase of ~ 1 °C at the air temperature. In the canopy level 
                         analysis, a decrease in EVI (browning effect) was observed during 
                         the dry season, with a corresponding increase (greening effect) 
                         occurring in the rainy season. The EVI was a better indicative of 
                         leaf maturity, since it presented increase between three and five 
                         months after the peak of new leaf production seen with Gcc. The 
                         functional attributes P50, \πTLP and the predominant 
                         anisohydric behavior (low stomatal regulation) of the monitored 
                         tree species indicated that the forest presents a moderate degree 
                         of resistance to drought in the context of the study plot, 
                         considering all classes of diameter. The average annual growth of 
                         the trees was 0.18 ą 0.15 cm.year-1, with lower values during xiv 
                         the dry season, and smaller increment among the species of 
                         diameter <20 cm. Functional attributes have shown that thinner 
                         trees are also less resistant to drought. Water was the main 
                         limiting factor for forest dynamics at the canopy level, since EVI 
                         (Rē = 0.37) and total litter (Rē = 0.56) presented significant 
                         correlation with precipitation (\α = 0.05), and also at the 
                         physiological level due to the significant correlation between 
                         tree growth and precipitation (Rē = 0.19) and soil moisture (Rē = 
                         0.24) (\α = 0.05). During the occurrence of the El-Niņo 
                         episode in 2015/16, \ΔEVI and \ΔGcc negative were 
                         observed. However, effects on growth were seen after El Niņo, 
                         suggesting that the frequency of negative precipitation anomalies 
                         may be critical to the forest, regardless of the intensity of the 
                         drought.",
            committee = "Shimabukuro, Yosio Edemir (presidente) and Borma, Laura de Simone 
                         (orientadora) and Wagner, Fabien Hubert and Araujo, Alessandro 
                         Carioca de and Moura, Yhasmin Mendes de",
         englishtitle = "Analysis of seasonal and interannual response of forestry dynamics 
                         using MODIS/MAIAC sensor data and in situ measurements in a forest 
                         fragment in Southwest of the Amazon",
             language = "pt",
                pages = "93",
                  ibi = "8JMKD3MGP3W34R/3RK95K8",
                  url = "http://urlib.net/ibi/8JMKD3MGP3W34R/3RK95K8",
           targetfile = "publicacao.pdf",
        urlaccessdate = "27 abr. 2024"
}


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