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Understanding the impact of Asian soybean rust on soybean yield is of great importance in the crop simulation model for this crop become it is possible to predict yield using different sowing dates and growth conditions. The goal of this study were to evaluate the performance of two soybean cultivars in Triângulo Mineiro/Alto Paranaíba, MG, Brazil and the effects of soybean rust on the yield of these cultivars using the CSM-CROPGRO Soybean model. Two soybean cultivars NK 7074 (early) and UFUS-Impacta (medium late), which differ in their development cycles, were growing in Uberaba city during the 2009/2010 growing season. The validation for cultivar UFUS-Impacta was conducted comparing the measured and simulated yield data considering three different sowing dates in the Uberlândia city during the 2002/2003 growing season. Daily meteorological data obtained from six meteorological stations of the National Institute of Meteorology (INMET ). To determine the performance of the soybean cultivars and the effect of soybean rust on yield, three different scenarios were used: no occurrence of rust (NOR) and occurrence of rust with inoculum concentrations of U5.000 and U10.000 urediniospores/mL. For all environments studied, the early cultivar had the best performance than the medium late cultivar. Soybean rust had the most effect on yield for the U10.000 scenario than for the U5.000 scenario. The best soybean performance occurred for Araxá and Uberaba cities. The South-Southeast area of the Triângulo Mineiro/Alto Paranaíba region was the most sensitive to the effect of rust on yield compared to the North region.

Local governments in Brazil believe that biodiesel can be the motor of rural development in impoverished semi-arid regions. Such policies are increasingly challenged by the search for sustainable biodiesel crop options that best match farmers’objectives. Our aim is to explore socioeconomically and environmentally sustainable biodiesel crop options for family farms in the North of Minas Gerais, Brazil. A computer programme (TechnoGIN) was used to systematically generate all combinations of crop options with different production techniques. Based on previously done typology, a survey was conducted in the municipality of Montes Claros, further data was collected with expert knowledge, crop models, literature and field experiments. Calculations have been done for current (maize and beans) and future oriented land use systems (biodiesel crops). Socioeconomic and environmental advantages of biodiesel crops are not self-evident. Integrated food-energy systems might be a way of copping with economic and environmental uncertainties.

In recent years, crop models have increasingly been used to simulate agricultural features. The DSSAT (Decision Support System for Agrotechnology Transfer) is an important tool in modeling growth; however, one of its limitations is related to the unaccounted- for effect of diseases. Therefore, the goals of this study were to calibrate and validate the CSM CROPGRO-Soybean for the soybean cultivars M-SOY 6101 and MG/BR 46 (Conquista), analyze the performance and the effect of Asian soybean rust on these cultivars under the environmental conditions of Viçosa, Minas Gerais, Brazil. The experimental data for the evaluation, testing, and adjustment of the genetic coefficients for the cultivars, M-SOY 6101 and MG/BR 46 (Conquista), were obtained during the 2006/2007, 2007/2008 and 2009/2010 growing seasons. GLUE (Generalized Likelihood Uncertainty Estimation) was used for the estimation of the genetic coefficients, and pedotransfer functions have been utilized to estimate the physical characteristics of the soil. For all of the sowing dates, the early season cultivar, M-SOY 6101, exhibited a lower variance in yield, which represents more stability with regard to the interannual climate variability, i.e., the farmers who use this cultivar will have in 50% of the crop years analyzed, a higher yield than a late-season cultivar. The MG/BR 46 (Conquista) cultivar demonstrated a greater probability of obtaining higher yield in years with favorable weather conditions. However, in the presence of the Asian soybean rust, yield is heavily affected. The early cultivar, M-SOY 6101, showed a lower risk of being affected by the rust and consequently exhibited less yield loss considering the scenario D90 (condensation on the leaf surface occurs when the relative humidity is greater than or equal to 90%), for a sowing date of November 14. Made available in DSpace on 2012-09-14T01:06:40Z (GMT). No. of bitstreams: 1 v71n2a211.pdf: 2121696 bytes, checksum: c4f0bb8b35103067ca668deb29b37ca9 (MD5) Previous issue date: 2012-09-12

Made available in DSpace on 2018-08-24T22:53:11Z (GMT). No. of bitstreams: 1 tese_4362_.pdf: 2733607 bytes, checksum: ae4c4942e9fdfc938d3bd56d8eb306a0 (MD5) Previous issue date: 2010-08-26 A presença de populações algais nos reservatórios torna mais problemática a operacionalidade dos sistemas de tratamento e pode causar impactos negativos na qualidade das águas distribuídas ao gerar sabores e odores na água e interferir no processo de clarificação. Além disto, uma das grandes preocupações ambientais e de saúde pública em lagos e represas e a floração de algas e cianobactérias produtoras de toxinas. Em águas de abastecimento, a matéria orgânica natural, as algas/microalgas e as cianobactérias e seus metabólitos, inclusive suas toxinas, são os principais precursores com os quais os halogênios reagem para formar subprodutos da cloração, entre estes os trialometanos. O processo de clarificação utilizando o sistema de flotação vem sendo utilizado para remoção de algas, cianobactérias e suas toxinas em substituição ou conjuntamente com os processos de decantação e filtração direta. Este estudo consistiu da avaliação, em escala de bancada, dos processos de coagulação e floculação com sulfato de alumínio, flotação por ar dissolvido (FAD), inter-oxidação com cloro, filtração em areia e desinfecção com cloro, com o objetivo de investigar a remoção de fitoplâncton e a formação de trialometanos em águas de abastecimento com presença de microalgas e cianobactérias. O estudo de coagulação com sulfato de alumínio resultou em regiões semelhantes de remoção (pH 6,3 e 6,5 e 25 a 35mg/L Al2(SO4)3) dos parâmetros cor aparente e cor real e turbidez para os períodos de seca (71%) e de chuvas (93%). Na otimização da flotação os resultados indicaram uma melhor remoção do material particulado (95%) e cor real (74%) na velocidade ascensional de 5cm/min. Os testes de inter-oxidação resultaram em baixa demanda de cloro, indicando a eficiência da flotação na remoção da matéria orgânica. A caracterização da água do manancial Duas Bocas mostrou qualidade de água satisfatória para águas de abastecimento no período observado. Na avaliação qualiquantitativa do fitoplâncton foram registrados 22 táxons, sendo a Classe Cyanophyceae a mais representativa em riqueza e em densidade relativa total nos dois meses de estudo, destacando o domínio das espécies Synechococcus nidulans e Anabaena sp. Esta última apresenta potencial de produção de neurotoxinas e hepatotoxinas, 9 dos 15 gêneros listados são mencionados como causadores de problemas operacionais como gosto, odor, colmatação dos filtros, entre outros. No estudo comparativo entre duas linhas de tratamento, apesar de um maior gasto com coagulante e alcalinizante, o tratamento 2 (30mg/L Al2(SO4)3 em pH 6,4) mostrou-se adequado nos dois meses estudados (maio e junho). A inter-oxidação apresentou baixa eficiência de remoção dos parâmetros cor aparente, turbidez e absorbâncias 254 e 665, nos tratamentos 1 e 2. O meio filtrante misto, composto com de grãos de areia de tamanho 1,20 a 0,60mm (70%) e 0,60 a 0,30mm (30%) seguido de desinfecção com cloro (5mg Cl2/mL), mostrou-se eficiente na remoção dos parâmetros analisados para os quatro tratamentos estudados, compensando os valores menores de remoção observadas nas etapas anteriores. Todos os tratamentos estudados apresentaram resultados positivos para a formação de clorofórmio e bromodiclorometano, porém abaixo dos limites estabelecidos pela Portaria MS 518/04 para TTHM.

Based upon coupled climate simulations driven by present day and glacial boundary conditions, we demonstrate that although the ice sheet topography modifications during the glacial period are primarily placed in the Northern Hemisphere (NH), a climate simulation that employs the ICE-5G glacial topography delivers significantly enhanced climate anomalies in the Southern Hemisphere (SH) as well. These conditions, in association with climate anomalies produced by the modification of the atmospheric CO² concentration characteristic of the Last Glacial Maximum (LGM) interval, are shown to be the primary forcing of the SH climate during this epoch. Climate anomalies up to -6°C over the Antarctic region and -4°C over South America are predicted to occur in respect to present day conditions. Accompanying the SH cooling in the LGM simulation there exists a remarkable reduction in the specific humidity, which in turn enforces the overall Southern Hemisphere cooling due to the weaker greenhouse capacity of the dry atmosphere. Com base em simulações numéricas conduzidas com condições de fronteiras características dos períodos glaciais e atual, demonstra-se que embora as maiores anomalias da topografia da Terra no período glacial estejam no Hemisfério Norte, esta inclusão dos blocos de gelo leva a substanciais mudanças na circulação atmosférica austral para aquela época, indicando uma forte teleconexão inter-hemisférica. Em associação com a redução nos níveis de carbono atmosférico para 200 ppm, anomalias de temperatura de -6°C em torno da região antártica, e -4°C no continente sul-americano são simuladas para o último máximo glacial (UMG) em relação a condições atuais. Concomitantemente, o UMG é caracterizado por uma drástica redução na umidade específica, que por sua vez intensifica o esfriamento inicial devido à mais fraca capacidade de estufa da atmosfera mais seca.

Global climate during the last glacial period was punctuated by abrupt warmings and occasional pulses of freshwater into the North Atlantic that disrupted deepwater production. These massive freshwater pulses known as Heinrich events arose, in part, from instabilities within the Laurentide ice sheet. Paleoevidence from the North Atlantic suggests that these events altered the production of deep water and changed downstream climate throughout the Northern Hemisphere. In the tropical western Pacific sea, surface temperatures and salinity varied together with ocean and climate changes at high latitudes. Here we present results from coupled modeling experiments that shed light on a possible dynamical link between the North Atlantic Ocean and the western tropical Pacific. This link involves a global oceanic standing wave pattern brought about by millennial-scale glacial density variations in the North Atlantic, atmospheric teleconnections triggered by meridional sea surface temperature gradients, and local air-sea interactions. Furthermore, our modeling results are compared with hydrological records from the Cariaco basin, the Indian Ocean, the Sulu Sea, and northern Australia.

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