779 resultados para fertilizantes


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Mode of access: Internet.

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Mode of access: Internet.

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Contiene: t. 1: Dépositions - t. 2: Rapport de la commission...

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Mode of access: Internet.

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Residential homegardens have environmental and social roles in the urban environment. These green spaces can potentially minimize the impacts caused by the growth of cities, being an alternative to connect fragmented areas or offer refuge to wildlife and therefore support the conservation of biodiversity. In addition, the homegardens demonstrate a leading role in increasing human well-being by promoting socialization opportunities, contact with nature, local culture as well as improvements in food security for the urban families. Nevertheless, it is still unclear what specific characteristics of homegardens can act effectively in the conservation of the biodiversity, as well as in the construction of food security and well being of the homegardeners and their families. The first chapter of this thesis analyzed the diversity of plant species (native and exotic) and assessed the contribution of different types of urban gardens (ornamental and forest gardens alike) in the presence of wildlife such as birds, monkeys and lizards. In the second chapter we evaluated the contribution of those gardens to the welfare and food security of their owners. In order to do this, 41 gardens were visited in Pium, a southern coastal town in the northeastern Brazil, which also happens to be in a periurban region undergoing rapid urban expansion and pressure from the real estate market. We surveyed the planned biodiversity and fauna associated with homegardens. The data related to food security and welfare were sampled through interviews with the person in charge of taking care of the gardens. These interviews covered issues on the supply of food from the garden and absence of chemical products, as well as aspects of the GNH indicator (Gross National Happiness). The results showed that these homegardens generally contribute little to the maintenance of native plant species (native species = 29/ total = 187). From its main features, the gardens were classified as ornamental, forest gardens and forest farms. These groups had a different effect on the presence of the animals studied and the last two contained most of the sampled native species. The diversity of plants and trees was a good predictor of the presence of birds and monkeys. Thus, the contribution of yards for the conservation of biodiversity depends on the type of garden: some even can have negative effects on conservation. These results can direct new approaches to detailed understanding of gardens and also of public policies applied to urban planning. The results of the second chapter showed that the two types of forest gardens contributed to household food security, for providing food and medicinal herbs, which mostly did not have pesticides and chemical 12 fertilizers. But the three groups of gardens are important components for the well being of their stakeholders. Gardens help promote the transmission of knowledge on agriculture, socialization, contact with nature and bring up feelings related to peace and harmony. Thus, forest gardens can be considered important means to get through public projects and policies designed to encourage biodiversity and promote food security and well-being in urban areas

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On the basis of human evolution and the population increase was necessary, the emergence of new sources of energy, the development of new products and technologies. One such product, object of the industry revolution and of great importance to the development of humanity is the oil, a substance composed primarily of hydrocarbons which give rise to several other products as fuels, lubricants, polymers, solvents, cooking gas, asphalt for roads, fertilizers, medicines, paints, among other. However, mishandling this product may cause leaks and spills that generate huge damages to the environment and the economy. Soon, with the purpose of contributing to decrease is problematic, in this master's work was carried out an intensive search of the possible potential of the fibers of Ceiba pentandra (L.) "Kapok" and Calotropis Procera as bioadsorbents of petroleum in water. The choice of these fibers is due to surface properties such as oleophylics and hydrophobic, their buoyancy and yet, being biodegradable natural polymers derived from the Brazilian Northeast. This research was used experimental planning with response surface methodology (RSM) with the software Design Expert. The results were statistically efficient, obtaining a R2= 0.9995 for Calotropis Procera and a R2= 0.9993 for Kapok. And that, both fibers showed adsorption efficiency, removing more than 80% petroleum in water static and dynamic state.

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Reservoirs are artificial ecosystems intermediate between rivers and lakes widely used in the Brazilian semiarid region as a way to provide water supply due to the said region’s water scarcity. The use of water from these supply sources for multiple uses, along with occupation and utilization of its riparian zone without proper management, directly influences the increased nutrient flow into aquatic environments, there with contributing to the acceleration of eutrophication. The semi-arid region is characterized by peculiar weather conditions, such as severe evaporation, high temperatures with little variation throughout the year and long water residence time, making it susceptible to prolonged drought occurrence, which tends to concentrate the nutrients in reservoirs, which favors the development of eutrophic conditions. Moreover, it is common soil use and occupation by carrying out activities with potential environmental impact on natural resources such as agriculture, livestock farming and lack of sanitation. The aim of this study is both to evaluate the water quality of the Cruzeta Reservoir, located in the semiarid region of Rio Grande do Norte, during a prolonged drought period, and assess the quality of its riparian zone soil under different uses, by monitoring physical-chemical variables. Along the prolonged drought, high levels of turbidity, suspended solids, nutrients and chlorophyll a were verified as present, therefore featuring low water quality. In the riparian zone of Cruzeta Reservoir, the areas under use of agriculture and livestock farming appeared as one of the main diffuse sources of nutrients to the said reservoir, featuring the highest levels of phosphorus and nitrogen in the soil, originated from decomposition of animal excreta and from the use of fertilizers, creating a tendency to increased eutrophication of such water supply source. The indicators of water and soil quality are useful for monitoring and evaluating the conservation status of natural resources, allowing the control and mitigation of the reservoir eutrophication process. This study confirmed the hypothesis that the reduction of water level, resulting from prolonged drought event, aggravates the symptoms of eutrophication; and also that using the soil under severalways modifies the physic chemical properties of the soil, having livestock farming and agriculture as the usages with greatest potential towards yielding P and N to the aquatic environment.

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Nitrogen (N) is one of the major nutrients nutrients absorbed in corn crops, for this reason, nitrogen based fertilizers are expensive and suffer large losses to the environment. Therefore, a diversity of fertilizers, known as special or of enhanced efficiency fertilizers, has been commercialized. The aim of this study was to evaluate the effect of different sources and levels of nitrogen fertilization in coverage, for agronomic characteristics and corn grain productivity, cultivated in the Cerrado region. The experiment was installed in 2015, in Monte Carmelo-MG. The experimental design utilized was a RCBD with four replications. The treatments consisted of five N sources (common urea, polymerized urea, urea combined with NBPT (thiophosphate N-n-butiltriamida or N-n-butiltriamida of thiophosphoric acid), organomineral combined or not with NBPT), five topdress N levels (40, 80, 120, 160 and 200 kg ha-1) and a control (no N topdressing). The evaluated parameters were: the first spike insertion height (FSIH), plant height (PH), stem diameter (DC), number of rows per spike (RS), number of grains per row (GR), spike length (SL), spike diameter (SD), prolificacy (EP), 1,000-grain weight (TGW), leaf chlorophyll index (LCI), content of foliar nutrients, dry matter in aerial part of the plant (DM) and productivity (PG). The results showed that, with the exception of stem diameter, there was no significant statistical difference between sources of nitrogen, indicating that the organomineral source is as efficient as a mineral source. Regardless of the source, the addition of N fertilizers in increasing doses promoted enhanced development of corn plants, increased chlorophyll content, stem diameter, leaf N content, crude protein and productivity. For most phytotechnical features, there was no significant statistic difference in treatments compared to control.

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Faced with an agribusiness expansion scenario and the increase in fertilizer consumption due to the exponential growth of the population, it is necessary to make better use of existing reserves, by obtaining products of better quality and in adequate quantities to meet demand national. In Tapira Mining Complex, Vale Fertilizantes, the phosphate concentrate is produced with content of 35.0% P2O5 from ore with content of about 8.0% P2O5, which are intended to supply Complex Industrial Uberaba and Araxá Minero Chemical Complex for the production of fertilizers. The industrial flotation step responsible for the recovery of P2O5 and hence the viability of the business is divided into the crumbly, grainy and ultrathin circuits, and, friable and granular concentrate comprise the conventional concentrated. Today only 14.7% of the mass which feeds the mill product becomes, the remainder being considered losses in the process, and the larger mass losses are located in the waste of flotation, representing 42.3%. From 2012 to 2014, the daily global mass recovery processing plants varied from 12.4 to 15.9% while the daily metallurgical recovery of P2O5 from 48.7 to 82.4%. By the degree of variability, it appears that the plant operated under different conditions. Seen this, this study aimed to analyze the influence of operational and process variables in P2O5 mass and metallurgical recoveries of industrial flotation circuits of grainy, crumbly and ultrathin. And besides was made an analysis of the effect of ore variables, as degrees, hardnesse and the ore front 02 percentage, in global recoveries of processing plant and the effect of dosages of reagents in the recoveries obtained from the bench flotation using the experimental design methodology. All work was performed using the historical database of Vale Fertilizantes of Tapira-MG, where all independent variables were dimensionless as the experimental range used. To make the statistical analysis it used the response surface technique and the values of the independent variables that maximize recoveries were found by canonical analysis. In the study of industrial flotation circuit crispy were obtained from 41.3% mass recovery and 91.3% metallurgical recovery P2O5, good values for the circuit, and the highest recoveries occur for solids concentration of the new flotation power between 45 and 50%, which values are assigned to the residence time of the pulp in cells and industrial flotation columns. The greater the number of ore heaps resumed on the higher the mass recovery, but in this scenario flotation becomes unstable because there is enormous weight variation in the feed. Higher recoveries are obtained for mass depressant dosage exceeding 120 g / t for synthetic collector dosage of 11.6%. In the study of industrial flotation circuit of the granulate were obtained 28.3% to 79.4% mass recovery and metallurgical recovery of P2O5 being considered good values for the circuit. Higher recoveries are obtained when the front ore 02 percentage is above 90%, because the ore of this front have more clear apatite. Likewise recoveries increase when the level of pulp rougher step is highest due to the high mass of circulating step receives loads. In the analysis of industrial flotation circuit of the ultrafine were obtained 23.95% of mass recovery, and the same is maximized to depressant dosage and the top collector 420 and 300 g / t, respectively. The analysis of the influence of variables ore, it was observed that higher recoveries are obtained for ores with P2O5 content above 8.0%, Fe2O3 content in the order of 28% forward and 02 of ore percentage of 83%. Hard ore percentage has strong influence on recoveries due to mass division in the circuit that is linked to this variable. However, the hard ore percentage that maximizes recoveries was very close to the design capacity of the processing plant, which is 20%. Finally, the study of the bench flotation, has noted that in friable and granular circuits the highest recoveries are achieved for a collector dosage exceeding 250 g / t and the simultaneous increase of collector dosage and synthetic collector percentage contributes to the increase recovery in the flotation, but this scenario is suitable to produce a concentrate poorer in terms of P2O5 content, showing that higher recovery is not always the ideal scenario. Thus, the results show the values of variables that provide higher recoveries in the flotation and hence lower losses in the waste.

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A atividade vitícola praticada na região do Douro é uma das mais importantes atividades agrícolas do país, não só devido a fatores socioculturais, como também pelo seu valor económico. A Região Demarcada do Douro (RDD) é uma das regiões vitícolas mais antiga do mundo, onde é produzido um dos vinhos generosos mais famosos do mundo, o Vinho do Porto. Contudo, no cultivo intensivo da vinha, o uso recorrente a pesticidas para o controlo de pragas das vinhas pode ter repercussões a nível da qualidade dos solos e dos cursos de água na envolvente às vinhas. O presente estudo foi desenvolvido numa área-piloto da sub-região Baixo Corgo da RDD, com o intuito de averiguar os possíveis efeitos e estimar os prováveis riscos ambientais promovidos pela viticultura. Foram selecionadas três vinhas, com idades de plantação distintas, onde foram recolhidas amostras de solos à superfície, tendo-se ainda feito uma recolha de amostras de água, sedimentos e águas intersticiais dos rios e da barragem na envolvente da área de estudo. Diferentes parâmetros químicos e físico-químicos foram analisados para uma avaliação global da área e prováveis fontes dos elementos. Especial destaque foi dado ao Cu, C, P, N, NO3 e S quer pelos teores anómalos e elevada variação espacial, quer pela sua importância como traçadores das atividades vitícolas e alguns como potenciais contaminantes. O Cu é o elemento potencialmente contaminante com mais destaque, visto que os seus teores são consideravelmente elevados nos solos e, a par, o P e N tendem a apresentar teores mais elevados na vinha mais velha, o que pode indicar efeitos de acumulação. Já os nitratos são mais elevados na vinha mais nova, visto que os processos de acumulação são mais difíceis neste caso devido à sua alta solubilidade e mobilidade. Apesar da elevada aplicação de S nas vinhas, os teores nestes solos são mais baixos do que nos solos sem atividades vitícolas, o que pode dever-se à sua baixa temperatura de sublimação e migração para níveis mais profundos dos solos. As baixas concentrações determinadas nos sedimentos e águas permitem concluir que as práticas vitícolas não parecem estar a interferir na qualidade dos mesmos. Contudo, novas campanhas de amostragem, abrangendo períodos sazonais distintos e próximos de épocas de aplicação de fertilizantes e pesticidas, deverão ser realizadas para validação temporal destes resultados.

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Una alternativa para la producción de biocombustibles consiste en la transformación de residuos lignocelulósicos, entre los que se encuentran biomasas maderables y no maderables. Colombia al ser un país rico en recursos agrícolas genera grandes cantidades de residuos provenientes de monocultivos como es el café, la caña de azúcar, el banano entre otros. Los residuos de banano se producen en zonas en donde el acceso a la energía es escaso y el tratamiento actual dado a estos residuos se centra en los biológicos buscando un producto que ayude a disminuir la aplicación de fertilizantes a la tierra. Con este proyecto se busca estudiar el potencial aprovechamiento de estos residuos para su implementación como biocombustible para la combustión y obtener energía a partir de los mismos. En este trabajo se realizó una caracterización de los residuos de la planta del banano (pseudotallo y hoja) mediante análisis termogravimétrico con una termobalanza TA Instrument TGA Q500IF, con el fin de definir el contenido de los tres componentes principales (hemicelulosa, celulosa y lignina). Los experimentos fueron realizados bajo condiciones de pirólisis y por medio de un algoritmo implementado con la herramienta Scilab. Además, el objetivo fue desarrollar una herramienta para determinar los contenidos de cenizas, contenido de humedad, contenido de residuo carbonoso y contenidos de hemicelulosa, celulosa y lignina para un reactor de combustión desde un análisis termogravimétrico. Los valores encontrados permiten concluir que tanto el pseudotallo como la hoja de la planta de banano son residuos potenciales de aprovechamiento en el proceso de combustión con fines de generación de energía.

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El proceso de acondicionamiento consiste en la saturación del sustrato con agua y posteriormente el lavado con un volumen de una disolución acuosa de MA entre 1 y 10 veces igual al volumen de compost. La mezcla peroxiacética (MA) es una disolución acuosa de peróxido de hidrógeno (PH) y ácido peracético (PAA) en distintas proporciones. La concentración de MA en la disolución acuosa que proponemos para su uso como acondicionamiento del compost está comprendida entre 1-10%. La concentración de peróxido de hidrógeno (H2O2) en el MA está comprendida entre 10-40% y la de ácido peroxiacético (C2H4O3) entre 1-10%. El método de acondicionamiento del compost con mezcla peroxiacética (MA) para su uso directo como sustrato agronómico tiene como objeto la obtención de compost de alta calidad, incluso con posibilidad de ser una alternativa a la turba de Sphagnum, presentando como aliciente que el coste medioambiental y económico de este proceso es menor que otras alternativas.

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The vineyard culture, in the Southwest of Paraná, has faced an evolution in recently years. However, some technical barriers has contained the expression of its full potential. Among which, the lack of scientific and technical support about the fertilization management and the fertility maintenance of production fields, is the most worrying. This fact, allied with the raising on the consumers demand for ecological correct products, are the motivations for the present study, whose main objective was to evaluate the effects of different fertilizer formulations, based on alternative nutrient sources, on grapevine yield and grape fruit quality, aiming at the improvement of those parameters and the maintenance of soil fertility. To achieve this goal, an experiment has been evaluated since 2008, at the experimental area of the Federal Technological University of Paraná, Campus Pato Branco, where ten treatments were being tested, combining or isolating shale derivates from other alternative nutrient sources. Those are the treatments: T1: Gafsa Rock Phosphate (GRP) + K2SO4; T2: GRP + RPB (Rock Powder Bioland®); T3: GRP + K2SO4 + LH (Laying Hen Litter); T4: GRP+ RPB + LH; T5: GRP + K2SO4 + MBR (Matrix Shale 3); T6: GRP + RPB + MBR; T7: GRP + K2SO4 + MBR + LH; T8: GRP + RPB + LH + MBR; T9: TSP (Triple Superphosphate) + Urea + KCl and T10: absolute control. The usage of fertilization, specially the alternative fertilization, improved soil fertility characteristics and also the yield on the last two evaluated harvests. The potassium sulfate improved the potassium availability on soil, while improved yield on the last three harvests. The MBR improved the phosphorus availability, improved post-harvest conservation and improved the yield on the last evaluated harvest.