Submitted by Mario BC (mario@bc.ufrpe.br) on 2016-08-15T12:27:23Z No. of bitstreams: 1 Diogenes Virginio do Nascimento.pdf: 1474487 bytes, checksum: 048118961940a4468c5c60cb32deca19 (MD5) / Made available in DSpace on 2016-08-15T12:27:23Z (GMT). No. of bitstreams: 1 Diogenes Virginio do Nascimento.pdf: 1474487 bytes, checksum: 048118961940a4468c5c60cb32deca19 (MD5) Previous issue date: 2015-07-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This work is related to knowledge of Pedotransfer functions (PTF), enabling an understanding about water soil content influenced by soil properties and analyzes to generate PTFs. This study aimed was proposed pedotransfer functions (PTF) based on hydro-physical soil properties and organic carbon to estimate soil moisture. The study was conducted in the area owned by Santa Teresa Plant in Goiana City, PE (7º36'56 "S 34º59'19" W) with sugarcane crop (Saccharum spp) irrigated by Lateral Move System. Field capacity (θfc) and wilting point (θwp) were assumed by dependent variables. Sand, silt, clay, soil bulk density and organic carbon were adopted as independent variables. Pedotransfer functions generated in this study estimate soil moisture to matric potential at -10 kPa, equivalent to θfc, in sandy soils and at -33 kPa to clay soils and matric potential at -1.500 kPa to θwp in 0-20; 20-40 e 40-60cm soil depth. These functions were classified as “Point PTF”, since estimated specific points to matric potential to soil water retention. Statistical indices and graphic analyses (1:1 ratio) between model-predicted and observed data were used to evaluate PTFs performance. The following statistical indices were used: Correlation coefficient (r), Concordance index (d), Maximum error (ME), Square root mean squared error normalized (RMSE), Coefficient of residual mass (CRM), Mean absolute error (MAE), Performance Index (c) and Determination coefficient (R²). Statistical indices that evaluate generated models to estimate soil water content indicated high performance for most of PTFs and good correlation between observed and estimated values at matric potential studied in all soil layers analyzed. Thus, retention water estimated by PTFs can be an interesting alternative to support irrigation management at sugarcane. / Esta dissertação é referente aos conhecimentos sobre Funções de Pedotransferência (FPT), possibilitando um entendimento relacionado ao conteúdo de água no solo a partir das influências nas propriedades do solo e nas análises estabelecidas para gerar as FPTs. O objetivo deste trabalho foi gerar funções de pedotransferência com base em atributos físico-hídricos do solo e a relação do carbono orgânico para estimar a umidade do solo. O trabalho foi realizado na área pertencente à Usina Santa Teresa localizada no município de Goiana, PE (7º36’56”S 34º59’19”W), em área cultivada com cana-de-açúcar (Saccharum spp) irrigada por sistema Lateral Móvel Linear. As variáveis adotadas como dependentes foram umidade na capacidade de campo (θcc) e umidade no ponto de murcha permanente (θpmp) e as variáveis independentes foram areia, silte, argila, densidade do solo e carbono orgânico. As funções de pedotransferência foram geradas a partir do método de regressão linear múltipla aplicando a técnica de stepwise backward elimination para seleção das variáveis candidatas ao modelo. Assim, as FPT geradas estimam o conteúdo de água no solo equilibrada nos potenciais mátricos equivalentes à umidade na capacidade de campo de -10kPa para solos arenosos, -33kPa para solos argilosos e ao ponto de murcha permanente de -1500kPa, nas camadas de 0-20; 20-40 e 40-60cm, totalizando 99 amostras. Essas funções foram classificadas como FPT pontuais, uma vez que, estima pontos específicos aplicados nas tensões de interesse para retenção de água no solo. O desempenho das Funções de pedotransferência foram analisadas graficamente pela relação 1:1, entre os dados estimados versus dados observados e por meio dos seguintes indicadores estatísticos: Coeficiente de correlação (r), Índice de concordância (d), Erro máximo (ME), Raiz quadrada do erro médio quadrático normalizado (RMSE), Coeficiente de massa residual (CRM), Erro absoluto médio (EAM), Índice de desempenho (c) e coeficiente de determinação (R²). Os índices estatísticos, que avaliam os modelos gerados para estimar a umidade volumétrica no solo estudado, apresentaram valores que indicam elevado desempenho para a maioria das FPTs e boa correlação entre os valores observados e estimados nas tensões estudadas e em todas as camadas de solo analisadas. Assim, a estimativa da retenção de água no solo por meio da FPTs apresenta-se como uma alternativa para auxiliar as técnicas adotadas no manejo de irrigação da cana-de-açúcar.

This study investigates the upper ocean circulation along the west Australian coast, based on recent observations (WOCE ICM6, 1994/96) and numerical output from the 1/6 degree Parallel Ocean Program model (POP11B 1993/97). Particularly, we identify the source regions of the Leeuwin Current, quantify its mean and seasonal variability in terms of volume, heat and salt transports, and examine its heat balance (cooling mechanism). This also leads to further understanding of the regional circulation associated with the Leeuwin Undercurrent, the Eastern Gyral Current and the southeast Indian Subtropical Gyre. The tropical and subtropical sources of the Leeuwin Current are understood from an online numerical particle tracking. Some of the new findings are the Tropical Indian Ocean source of the Leeuwin Current (in addition to the Indonesian Throughflow/Pacific); the Eastern Gyral Current as a recirculation of the South Equatorial Current; the subtropical source of the Leeuwin Current fed by relatively narrow subsurface-intensified eastward jets in the Subtropical Gyre, which are also a major source for the Subtropical Water (salinity maximum) as observed in the Leeuwin Undercurrent along the ICM6 section at 22 degrees S. The ICM6 current meter array reveals a rich vertical current structure near North West Cape (22 degrees S). The coastal part of the Leeuwin Current has dominant synoptic variability and occasionally contains large spikes in its transport time series arising from the passage of tropical cyclones. On the mean, it is weaker and shallower compared to further downstream, and it only transports Tropical Water, of a variable content. The Leeuwin Undercurrent carries Subtropical Water, South Indian Central Water and Antarctic Intermediate Water equatorward between 150/250 to 500/750 m. There is a poleward flow just below the undercurrent which advects a mixed Intermediate Water, partially associated with outflows from the Red Sea and Persian Gulf. Narrow bottom-intensified currents are also observed. The 5-year mean model Leeuwin Current is a year-round poleward flow between 22 degrees S and 34 degrees S. It progressively deepens, from 150 to 300 m depth. Latitudinal variations in its volume transport are a response to lateral inflows/outflows. It has double the transport at 34 degrees S (-2.2 Sv) compared to at 22 degrees S (-1.2 Sv). These model estimates, however, may underestimate the transport of the Leeuwin Current by 50%. Along its path, the current becomes cooler (6 degrees C), saltier (0.6 psu) and denser (2 kg m -3). At seasonal scales, a stronger poleward flow in May-June advects the warmest and freshest waters along the west Australian coast. This advection is apparently spun up by the arrival of a poleward Kelvin wave in April, and reinforced by a minimum in the equatorward wind stress during July. In the model heat balance, the Leeuwin Current is significantly cooled by the eddy heat flux divergence (4 degrees C out of 6 degrees C), associated with mechanisms operating at submonthly time scales. However, exactly which mechanisms it is not yet clear. Air-sea fluxes only account for ~30% of the cooling and seasonal rectification is negligible. The eddy heat divergence, originating over a narrow region along the outer edge of the Leeuwin Current, is responsible for a considerable warming of a vast area of the adjacent ocean interior, which is then associated with strong heat losses to the atmosphere. The model westward eddy heat flux estimates are considerably larger than those associated with long lived warm core eddies detaching from the Leeuwin Current and moving offshore. This suggests that these mesoscale features are not the main mechanism responsible for the cooling of the Leeuwin Current. We suspect instead that short lived warm core eddies might play an important role.