Navegando por Autor "Mello, Carlos Rogério de"
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Item Análise da condutividade hidráulica saturada em uma Floresta de Cedro, Madrid, Espanha(Revista Agrogeoambiental, 2018-09) Junqueira, Rubens; Mello, Carlos Rogério de; Oliveira, Alisson Souza de; Alves, Geovane Junqueira; Aires, Uilson Ricardo VenâncioA condutividade hidráulica saturada do solo (K0) é de grande importância para a hidrologia, especialmente no contexto da infiltração, onde apresenta grande influência nas condições de geração de escoamento superficial direto, tendo como consequências a formação de inundações, erosão do solo e transporte de sedimentos. Além disso, tem papel fundamental na agricultura, por contribuir na infiltração e disponibilização de água para as plantas, e também na conservação do solo e do meio ambiente. Diante do exposto, o objetivo deste trabalho foi estimar e analisar o comportamento da condutividade hidráulica saturada do solo associada aos seus atributos físicos e declividade e avaliar o escoamento superficial direto, em uma área de floresta de Cedrus deodara, em Madrid, na Espanha. Para tanto, foram realizados testes de infiltração com o método dos anéis concêntricos em três pontos na área de estudo, a fim de obter dados que foram ajustados pelo modelo de Horton para estimar a condutividade hidráulica saturada do solo, e também foram realizados testes com um simulador de chuvas a fim de determinar o coeficiente de escoamento superficial. Foram retiradas amostras deformadas do solo para determinação de seus atributos físicos. Os resultados mostraram que o modelo de Horton foi adequado para estimar a condutividade hidráulica saturada do solo. Os valores dos atributos físicos do solo e a declividade influenciaram a condutividade hidráulica saturada do solo. A matéria orgânica associada à declividade do solo proporcionaram os maiores valores de K0. O escoamento superficial direto apresentou relação inversa à condutividade hidráulica saturada do solo.Item Daily rainfall disaggregation for Tocantins State, Brazil(Revista Ambiente & Água, 2017-05-08) Silva Neto, Virgilio Lourenço da; Viola, Marcelo Ribeiro; Silva, Demetrius David da; Mello, Carlos Rogério de; Pereira, Silvio Bueno; Giongo, MarcosIn order to design effective Brazilian hydraulic structures, it is necessary to obtain data relating to short-duration intense rainfall from historical series of daily rainfall. This recurring need can be fulfilled by rainfall disaggregation methodology. The objective of this study was to determine the intense rainfall disaggregation constants for the State of Tocantins and to compare these constants with those obtained for other regions of Brazil. For the modeling of the frequency of intense rainfall of different durations of less than 24 hours, the Gumbel probability distribution (GPD) was employed using rainfall series from 10 locations in Tocantins state. The results showed that the GPD was adequate by the Kolmogorov-Smirnov and Chi-square tests. The disaggregation constants presented low variability values for different return periods (from 10 to 100 years); the values for Tocantins state are: h12h/h24h=0.93, h6h/h24h=0.86, h4h/h24h=0.82, h3h/h24h=0.78, h2h/h24h=0.72, h1h/h24h=0.61, h50min/h1h=0.92, h40min/h1h=0.83, h30min/h1h=0.68, h20min/h30min=0.76 e h10min/h30min=0.46. The comparison of the results with those from studies developed for other Brazilian regions showed variations of up to -62.30%, allowing us to conclude that the use of local constants is important in the process of rainfall disaggregation.Item Hydrosedimentological modeling in a headwater basin in Southeast Brazil(Sociedade Brasileira de Ciência do Solo, 2020-07-20) Mauri, Eliete Nazaré Eduardo; Viola, Marcelo Ribeiro; Norton, Lloyd Darrell; Owens, Phillip Ray; Mello, Carlos Rogério de; Pinto, Leandro Campos; Curi, NiltonHydrosedimentological modeling is a useful tool to predict the water dynamic in a basin and for water resources management. This study aimed to i) evaluate the ability of Soil and Water Assessment Tool (SWAT) to model sediment load and continuous monthly streamflow in the Mortes River Basin (MRB) in Southeastern Brazil; ii) estimate the sediment yield spatially distributed by sub-basins; iii) estimate the sediment load export to the Funil Hydroelectric Power Plant reservoir (FHPP), located in the MRB outlet. For the sensitivity analysis, calibration, and uncertainty analysis of the model, a semi-automatic calibration in SWAT-CUP version 5.1.6 software with the “Sequential Uncertainty Fitting” algorithm was used. To evaluate the ability of SWAT to reproduce the continuous MRB monthly streamflow and sediment load, statistical indexes, and graphical analyses were used to compare the simulated and observed data. For the sediment evaluation, a spatial and temporal comparison of sediment yield maps was used as well as the sediment yield observed in sub-basins, aiming to identify the areas with a more significant contribution to the sediment generation in the basin. The results demonstrated that SWAT performed satisfactorily in simulating both monthly sediment load and streamflow. For discharge calibration, 99 % of the measured data were bracketed by the 95 % prediction uncertainty (95PPU), and for validation, 97 % of the data were bracketed by the 95PPU, which indicates proper bracketing of the measured data within model prediction uncertainty. Uncertainty analysis indicated that 95PPU could capture 78 % of the sediment loads measured during the calibration and 72 % of the measured data during the validation period at MRB. The hydrologic response unit with pasture and Argissolos (Ultisols), Neossolos Litólicos (Entisols), and Cambissolos (Inceptisols) combined with undulated relief were the main areas responsible for the highest sediment contributions. The sediment load delivered to the reservoir from its filling 2002 to 2015 was estimated in 6,682,704 m3 (16,706,761 Mg) (density of 2.5-Mg m-3) which value corresponded to 2.6 % of storage capacity (water plus sediment) in 14 years. These results are strategic since to become feasible identifying priority areas for soil and water conservation practices as well as useful information for water resources planning and management in the studied basin.Item Water footprint of the Sobradinho hydropower plant, Northeastern Brazil(Revista Ambiente & Água, 2018) Pereira, Silvio Bueno; Vieira, Nayara Paula Andrade; Bueno, Eduardo de Oliveira; Mello, Carlos Rogério deHydroelectricity is responsible for the greatest fraction of the electric energy generated in Brazil. The water footprint of hydropower plants (WFP) is an important indicator of the sustainable and efficient use of water resources. In this context, WFP of the Sobradinho Hydropower Plant was determined for the period from 2003 to 2012, taking into account the reservoir’s historical variation for the flooded area. To accomplish this, monthly series of electric energy production, flooded area, evaporation and evapotranspiration rates were used. Average gross and net evaporation were 2,031 and 1,577 mm year-1, respectively. The average power generation of this facility in the analyzed period was 462 MW, and the flooded area of its reservoir presented an average value of 3,054 km². Based on the monthly data, the gross and net water footprints were, respectively, 417 and 325 m³ GJ-1. Based on these results, it can be concluded that the changes in the reservoir’s area exert direct and important influence on the WFP estimates of the Sobradinho hydropower plant. The WFP estimates in this study were different from other studies that adopted a constant value of 4,214 km² for this reservoir’s area, which is taken based on the normal water level of the plant operation.