2015-08-272015-08-272008OLIVEIRA, Livia da Silva. Refinamento da representação de raízes no modelo de biosfera SiB2 em área de floresta na Amazônia. Orientador: José Henrique Cattanio. 2008. 66 f. Dissertação (Mestrado em Ciências Ambientais) - Instituto de Geociências, Universidade Federal do Pará, Museu Paraense Emílio Goeldi, Empresa Brasileira de Pesquisa Agropecuária, Belém, 2008. Disponível em: http://repositorio.ufpa.br:8080/jspui/handle/2011/6849. Acesso em: .https://repositorio.ufpa.br/handle/2011/6849The objective of this research was to study the sensitivity of the surface flows and soil hydrology in relation to the representation and distribution of roots in the biosfera model for upland forest in the “Amazônia”. The purpose was to evaluate the impact on the representativeness of the energy surface flows, considering the Amazon region seasonality supported by intensive measures carried through in a biological reserve (Biological Reserve in “Cuieiras” River, near Manaus). Eight simulations were conducted with the model of biosphere SiB2 (Simple Biosphere Model - version 2), where each simulation scenario represented a different scenery of roots distribution in a 4.0 m depth, divided in three layers: 0.5 m , 1.5 m and 2.0 m. The roots were distributed favoring the root’s concentration in the surface layer, after that, the intermediate layer and, finally, a concentration of roots below 2.0 m deep. The simulations were conducted for the period of 2003 to 2006, emphasizing the year of 2005 to evaluate the effect of the roots representation in the energy flows (latent heat - LE and sensitive heat - H) and carbon dioxide flow (F_CO2). From the integrated analysis of simulated flows with observational data, measured in the experimental site, was possible to perceive that a reduction in the rainfall for the year of 2005, although to have been lesser in the central part of the Amazon, led the decline in soil moisture, showing that the forest passed for a considerable period of water stress. The model represented the available energy with values very close to those observed, varying seasonally in agreement with the data measured in 2005. However, LE is overestimated during the rainy season, but it shows together with the CO2 flow, the reduction with soil moisture in the dry season period, while H is overestimated by 20 W.m-2 during all the simulated period. These results show that, apparently, the consideration of surface roots are more appropriate for regions with short dry season, as characterized the study area, and deep roots should promote the modeling of the processes of the surface areas with more pronounced dry season. With the results showing that it has necessity to get more information of soil physical properties, appropriate to the region conditions, so that other refinements are effective in distinguishing the behavior of tropical forests under different regimes of water availability in the soil.porAcesso AbertoDistribuição de raízesModelo de biosferaUmidade do soloFloresta tropicalSiB2Reserva Biológica do Cuieiras - AMManaus - AMAmazonas - EstadoAmazônia brasileiraDissertaçãoCNPQ::CIENCIAS AGRARIAS::AGRONOMIA::CIENCIA DO SOLO::FISICA DO SOLO