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@MastersThesis{Chaves:1992:PeEsBa,
               author = "Chaves, Marcelo de {\'A}vila",
                title = "Perspectivas de estimativa dos balan{\c{c}}os anuais 
                         h{\'{\i}}drico e de carbono em ecossistemas florestais {\`a} 
                         partir de um modelo biogeoqu{\'{\i}}mico florestal associado a 
                         t{\'e}cnicas de sensoriamento remoto orbital",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "1992",
              address = "Sao Jose dos Campos",
                month = "1992-07-09",
             keywords = "vegeta{\c{c}}{\~a}o, ecossistemas, {\'{\i}}ndice de {\'a}rea 
                         foliar, florestas, biogeoqu{\'{\i}}mica, modelos, carbono, 
                         classifica{\c{c}}{\~a}o de imagens, biogeochemistry, carbon 
                         cycle, conifers, ecosystems, environmental models, hydrological 
                         cycle, leaf area index, rain forest, image classification, 
                         vegetation, coniferas.",
             abstract = "Este trabalho tem por objetivo testar e avaliar o potencial de 
                         utiliza{\c{c}}{\~a}o de um modelo biogeoqu{\'{\i}}mico 
                         regional para representar os principais processos do ciclo 
                         hidrol{\'o}gico e do carbono de ecossistemas florestais de 
                         con{\'{\i}}feras, existentes em tr{\^e}s estados brasileiros, 
                         submetidos a condi{\c{c}}{\~o}es ambientais contrastes. Este 
                         modelo, denominado Forecos, tem como principal vari{\'a}vel de 
                         entrada o {\'{\i}}ndice de {\'a}rea foliar (IAF) que e um dos 
                         par{\^a}metros mais importantes na qualifica{\c{c}}{\~a}o de 
                         trocas de energia e massa de ecossistemas florestais. O IAF pode 
                         ser estimado por sensores remotos orbitais, pois e a vari{\'a}vel 
                         estrutural da vegeta{\c{c}}{\~a}o mais correlacionada com os 
                         {\'{\i}}ndices de vegeta{\c{c}}{\~a}o que s{\~a}o obtidos a 
                         partir de dados espectrais de imagens de sat{\'e}lites. Assim 
                         sendo, realizou-se o teste de sensibilidade das vari{\'a}veis do 
                         modelo e a simula{\c{c}}{\~a}o dos valores de IAF. Realizou-se 
                         tamb{\'e}m a classifica{\c{c}}{\~a}o digital de imagens 
                         {\'{\i}}ndice de vegeta{\c{c}}{\~a}o com o objetivo de obter 
                         padr{\~o}es de mapeamento desses {\'{\i}}ndices que devem 
                         refletir varia{\c{c}}{\~o}es nos valores de IAF embora valores 
                         absolutos n{\~a}o possam ser estimados nesta etapa do trabalho. 
                         Os resultados obtidos demonstram que o modelo, quando rodado de 
                         uma maneira geral, foi capaz de retratar diferen{\c{c}}as 
                         relativas entre os processos b{\'a}sicos dos ciclos 
                         hidrol{\'o}gicos e do carbono. O modelo conseguiu tamb{\'e}m 
                         descrever quantitativamente as intera{\c{c}}{\~o}es entre os 
                         fatores ambientais de cada {\'a}rea teste com os processos 
                         f{\'{\i}}sicos e biol{\'o}gicos que ocorreram nos ecossistemas 
                         florestais selecionados. Entretanto, a modelagem de alguns 
                         processos necessita ser revista ou ajustada e a 
                         valida{\c{c}}{\~a}o final do modelo requer medidas especificas 
                         de alguns par{\^a}metros e condi{\c{c}}{\~o}es iniciais. Os 
                         resultados obtidos nas classifica{\c{c}}{\~o}es de imagens 
                         digitais sugerem uma homogeneidade nos valores de IAF para as 
                         {\'a}reas teste o que, de certa forma, valida a 
                         utiliza{\c{c}}{\~a}o de um {\'u}nico valor de IAF na 
                         simula{\c{c}}{\~a}o realizada. ABSTRACT: This work is intended 
                         to test and to evaluate how well a regional biogeochemical model 
                         is able to represent the major processes of the hydrologic and 
                         carbon cycles of forest ecosystems of coniferous, growing up in 
                         three different climatic areas in Brazil. The model, named 
                         {"}Forecos{"} uses Leaf Area Index, LAI, as the main input 
                         variable. LAI is generally accepted as being the most import 
                         variable characterizing the exchange of energy and mass in forest 
                         ecosystems. There is substantial work done showing that LAI can be 
                         estimated from remotely sensed data, on the basis of the 
                         correlation that exists between this vegetation structure 
                         parameter and vegetation index, obtained by manipulation of data 
                         in different spectral bands of optical sensors. Simulations of LAI 
                         of the real world and sensitivity analysis on some critical 
                         parameters were used to test the suitability of the model to 
                         represent the processes modeled. By the means of digitat image 
                         classification, patterns of vegetation indexes were identified 
                         that should correspond to variations on LAI values, although 
                         absolute numbers could not be obtained at this step. The results 
                         have demonstrated that the model was able to show the relative 
                         differences for both hydrologic and carbon cycles for the three 
                         test sites studied. Besides that, the model was also capable of 
                         describing quantitatively the interactions between climatic 
                         parameters and biophysical processes in the ecosystems selected. 
                         Nevertheless, the mathematical formulation of some processes has 
                         to be revised or adjusted through fitting techniques. Finally a 
                         validation should be achieved with measurements of state variables 
                         and some independent measurements of net primary production and 
                         hydrologic variables. The results obtained from digital 
                         classification suggest that LAI values are homogeneous in all test 
                         sites. Then, the use of a unique regional value within the 
                         simulations realized is felt to be valid.",
            committee = "Soares, Jo{\~a}o Vianei (orientador/presidente) and Nobre, Carlos 
                         Afonso and Batista, Get{\'u}lio Teixeira and Vict{\'o}ria, 
                         Reynaldo Luiz",
           copyholder = "SID/SCD",
         englishtitle = "On the computation of carbon and water cycles in forest ecosystems 
                         using a biogeochemical model and remotely sensed data",
                label = "3189",
             language = "pt",
                pages = "166",
                  ibi = "6qtX3pFwXQZ3r59YD6/GP2Ds",
                  url = "http://urlib.net/rep/6qtX3pFwXQZ3r59YD6/GP2Ds",
        urlaccessdate = "13 nov. 2019"
}


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