875 resultados para Elementos tóxicos. Carbono orgânico total. Solo. Postos de revenda de combustíveis


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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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O uso e manejo do solo e da cultura são importantes condicionadores da variabilidade de atributos do solo. O trabalho foi desenvolvido em Selvíria (MS), com o objetivo de avaliar a variabilidade espacial do pH, potássio (K), cálcio (Ca), magnésio (Mg) e saturação por bases (V) em Latossolo Vermelho sob diferentes usos e manejos. Os solos foram amostrados em malha, com intervalos regulares de 2 m, perfazendo o total de 64 pontos, nas profundidades de 0,0-0,1 e 0,1-0,2 m, nas seguintes áreas: vegetação natural (Cerrado), plantio direto, plantio convencional e pastagem. As maiores variabilidades, medidas por meio do coeficiente de variação, foram observadas para K, Mg e Ca; o pH apresentou o menor coeficiente de variação nos diferentes usos e manejo do solo, e o atributo V, coeficiente de variação médio. Os sistemas preparo convencional e pastagem apresentaram os menores alcances quando comparado aos sistemas Cerrado e plantio direto.

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O uso do solo nem sempre dá lugar a um novo sistema ecológico sustentável, seja de lavouras, seja de pastagens. Com isso, solos utilizados intensamente e de forma inadequada são levados à degradação. Nesse sentido, este trabalho teve como objetivo estudar a influência do lodo de esgoto na recuperação de propriedades físicas de um Latossolo Vermelho degradado, cultivado há 2,5 anos com eucalipto (Eucalyptus citriodora Hook) e braquiária (Brachiaria decumbens) no município de Selvíria, MS. O delineamento experimental utilizado foi em blocos casualizados com seis tratamentos e quatro repetições. Os tratamentos foram: 1-vegetação de Cerrado; 2-solo exposto sem tratamento para recuperação; 3-solo cultivado com eucalipto e braquiária sem uso do lodo de esgoto e adubação mineral; 4-solo cultivado com eucalipto e braquiária com adubação mineral; 5-solo cultivado com eucalipto e braquiária com uso de 30 Mg ha-1 de lodo de esgoto; e 6-solo cultivado com eucalipto e braquiária com uso de 60 Mg ha-1 de lodo de esgoto. Nas camadas do solo de 0,00-0,05; 0,05-0,10; 0,10-0,20; e 0,20-0,30 m, foram estudadas as propriedades físicas do solo: macroporosidade, microporosidade; porosidade; e densidade do solo. Na braquiária foram avaliadas as matérias verde e seca e, no eucalipto, a altura média de planta e o DAP (diâmetro à altura do peito). Concluiu-se que o solo estudado está sendo recuperado por meio dos tratamentos estabelecidos. Dentre eles, destacam-se os tratamentos com a utilização do lodo, que influenciaram as propriedades físicas do solo, proporcionaram mais rendimentos de matérias verde e seca da braquiária e promoveram maior crescimento das plantas de eucalipto. O crescimento vegetal, a densidade do solo, a porosidade total e a macroporosidade foram os melhores indicadores da recuperação do solo.

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As propriedades físicas do solo podem ser alteradas mediante diferentes sistemas de manejo do solo e cultivo adotados. Assim, o presente trabalho foi desenvolvido em 2003/04, na região de Cerrado do Mato Grosso Sul, em Selvíria (MS), objetivando-se avaliar a produção de massa seca, porcentagem de recobrimento do solo e a influência de sucessões de culturas e sistemas de manejo nas propriedades físicas de um Latossolo Vermelho e na produtividade do feijoeiro de inverno irrigado. O delineamento experimental utilizado foi em blocos casualisados, em esquema de parcelas subdivididas, com quatro blocos. As parcelas foram constituídas pelos sistemas de manejo do solo - grade pesada, escarificador e plantio direto, e as subparcelas por seis sucessões implantadas no verão - milho, milho + mucuna-preta, milho + braquiária, soja, arroz e Crotalaria juncea. A cultura do feijão foi semeada após a colheita/manejo das plantas cultivadas no verão. C. juncea, milho + mucuna-preta, milho + braquiária e milho, independentemente do manejo do solo utilizado, constituem adequadas opções de sucessão de culturas, mediante alta produção de massa seca e recobrimento do solo. No plantio direto, comparado aos demais sistemas de manejo estudados, é causada compactação na camada superficial, mediante redução da macroporosidade. Com exceção da macroporosidade na camada mais superficial (0-0,1 m), as propriedades umidade, macroporosidade, microporosidade e porosidade total do solo não são influenciadas pelos sistemas de manejo do solo. Apesar de efeitos diferentes em alguns componentes de produção do feijoeiro devido a determinado manejo do solo ou sucessão de culturas, isso não repercute na produtividade do feijoeiro de inverno irrigado.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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A necessidade cada vez maior de alimentos, espaço e condições para sobrevivência faz com que as interferências antrópicas no ambiente sejam cada vez maiores. Solos intensivamente cultivados e de forma inadequada são degradados, assim como a construção de obras civis no meio rural sem atender à legislação pertinente tudo isso tem ocasionado problemas ao meio. Várias técnicas têm sido utilizadas para recuperar esses solos, sendo a principal delas a adição de MO. Contudo, informações sobre tempo para recuperação do solo, influência dos tipos de material orgânico e indicadores das alterações ainda são escassas. Este trabalho objetivou avaliar a recuperação das propriedades de um Latossolo Vermelho distrófico, de onde foi retirado material usado na terraplanagem e nas fundações da usina hidrelétrica de Ilha Solteira-SP, utilizando-se como indicadores de qualidade física a densidade do solo e a taxa de infiltração de água. A pesquisa foi feita em uma área onde se retirou uma camada de solo de 8,60 m. O delineamento experimental foi em blocos casualizados, com cinco repetições e cinco tratamentos: testemunha (solo exposto sem técnicas de recuperação); espécie arbórea gonçalo-alves (Astronium fraxinifolium Schott); gonçalo-alves + feijão-de-porco (Canavalia ensiformis); gonçalo-alves + nabo forrageiro (Raphanus sativus); e gonçalo-alves + gramínea (Brachiaria decumbens) + lodo de esgoto (60 Mg ha-1). A densidade do solo foi avaliada antes e 356 dias após a implantação dos tratamentos, e a infiltração de água no solo foi determinada 188 dias depois da instalação dos tratamentos. Concluiu-se que ocorrem melhorias na qualidade do solo quando efetuado o seu preparo e a adição de lodo de esgoto e adubos verdes. A densidade do solo e a infiltração de água do solo são bons indicadores na avaliação dessas melhorias. As diferentes fontes de MO adicionadas ao solo e a ação do preparo deste interagem de maneira semelhante na recuperação da sua qualidade, porém a combinação lodo de esgoto mais braquiária proporciona maior altura de planta da espécie gonçalo-alves.

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The processing of heavy oil produced in Brazil is an emergency action and a strategic plan to obtain self-sufficiency and economic surpluses. Seen in these terms, it is indispensable to invest in research to obtain new catalysts for obtaining light fraction of hydrocarbons from heavy fractions of petroleum. This dissertation for the degree of Doctor of Philosophy reports the materials preparation that combine the high catalytic activity of zeolites with the greater accessibility of the mesoporosity, more particularly the HZSM-5/MCM-41 hybrid, done by synthesis processes with less environmental impact than conventional ones. Innovative methodologies were developed for the synthesis of micro-mesoporous hybrid material by dual templating mechanism and from crystalline zeolitic aluminosilicate in the absence of organic template. The synthesis of hybrid with pore bimodal distribution took place from one-single organic directing agent aimed to eliminate the use of organic templates, acids of any kind or organic solvents like templating agent of crystalline zeolitic aluminosilicate together with temperature-programmed microwave-assisted, making the experimental procedures of preparation most practical and easy, with good reproducibility and low cost. The study about crystalline zeolitic aluminosilicate in the absence of organic template, especially MFI type, is based on use of H2O and Na+ cation playing a structural directing role in place of an organic template. Advanced characterization techniques such as X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Highresolution Transmission Electron Microscopy (HRTEM), Adsorption of N2 and CO2, kinetic studies by Thermogravimetric Analysis (TGA) and Pyrolysis coupled to Gas Chromatography/Mass Spectrometry (Pyrolysis-GC/MS) were employed in order to evaluate the synthesized materials. Achieve the proposed objectives, has made available a set of new methodologies for the synthesis of zeolite and hybrid micro-mesoporous material, these suitable for catalytic pyrolysis of heavy oils aimed at producing light fraction

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The soil tillage and the vegetable species have expressive effect on spatial variability of soil. The objective of this work was to study the spatial variability of some physical attributes of savannah soil (Oxisol) of Mato Grosso do Sul, Brazil, under different management. The soil samples were collected in a grid, with regular intervals of 2.0 m, total of 64 points, in the depths of 0-0.10 m and 0.10-0.20 m for bulk density and in the depths 0-0.15 m; 0.15-0.30 m; 0.30-0.45 m and 0.45-0.60 m for the soil resistance to the penetration and soil water content, in the areas with native vegetation (savannah), no-tillage, conventional system and pasture. The greatest variability measured through the variation coefficient and nugget effect was observed for the soil resistance to penetration. The no-tillage showed major range when compared to native vegetation, conventional system and pasture. The uses and managements induce, in the crescent order of no-tillage, conventional system and pasture towards degradation of soil physical attributes in relation to native vegetation.

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In Brazil, the upland rice Culture system is predominant, but its water supply depends of precipitation and its distribution. Sol-lie practices or disturbances on soil conditions may cause alterations that call be detected by microorganisms, which are quite sensitive. This experiment was developed to study microbiological alterations (microbial biomass carbon (MBC), released CO2 (C-CO2), metabolic quotient (qCO(2)) and mycorrhization), as well as alterations in soil fertility and productivity of upland rice, cultivated under different soil and water managements. Cultivar BRS Talento was used in the experiment. The experimental design was a completely randomized block design, with four replications, using three soil managements: no-tillage (NT), heavy disk + leveling disk harrowing (HL), and chisel plowing + leveling disk harrowing (CL), plus three water managements: no irrigation (WD0); water depth 1 (WD1), with irrigation at the reproductive and maturation periods; and water depth 2 (WD2), with irrigation throughout the rice cycle. Autochthones arbuscular mycorrhizal fungi proved to be sensitive to soil and water management. The NT presented the highest values for MO, Ca, SB and V% and the lowest for H+A1. This management, together with irrigation at the reproductive and maturation periods of BRS Talento cultivar, promoted goods results for crop yield and microbiology characteristics.

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As pastagens geralmente perdem seu potencial produtivo e vigor de rebrota nos primeiros anos, frequentemente associada à falta de adubação nitrogenada. O objetivo deste foi verificar o efeito de fontes e doses de adubação nitrogenada na atividade microbiana (carbono da biomassa microbiana e carbono do CO2 liberado) e na fertilidade do solo cultivado com Brachiaria brizantha cv. Xaraés. O delineamento experimental foi em blocos casualizados, em arranjo fatorial 3 x 4, envolvendo três fontes de nitrogênio (uréia, sulfato de amônio e Ajifer-L40) e quatro doses de nitrogênio (0, 100, 200 e 400 kg ha-1), nas profundidades 0 - 0,10 e 0,10 - 0,20 m, com três repetições. O aumento nas doses de nitrogênio, na camada 0,0 a 0,10 m de profundidade, reduziu os valores de pH, MO, K+, Ca2+, Mg2+, SB e V%. O Ajifer e a uréia elevaram os valores de Ca2+ na camada 0,10 - 0,20 m, e as doses de 100 e 200 kg ha-1 aumentaram os valores de Mg2+ e SB. em doses elevadas o sulfato de amônio acidificou o solo. A perda de carbono pela elevada atividade microbiana pode estar relacionado ao estresse metabólico devido à acidificação do solo. A aplicação de 100 kg ha-1 de nitrogênio acarretou as menores perdas de carbono pela atividade microbiana.

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O não revolvimento do solo com cultivo de adubos verdes na entressafra e o manejo da adubação nitrogenada alteram, geralmente, a dinâmica e a recuperação do N no sistema solo-planta. O objetivo deste trabalho foi avaliar a quantidade de N nativo do solo absorvido pelo milho em plantio direto, sob diferentes doses de N, em sucessão à crotalária (Crotalaria juncea), ao milheto (Pennisetum americanum) e à vegetação espontânea (pousio) em um Latossolo Vermelho no Cerrado. O estudo foi desenvolvido na fazenda experimental da Faculdade de Engenharia de Ilha Solteira-UNESP, Selvíria-MS, nos anos agrícolas 2001/02 e 2002/03. O delineamento experimental foi o de blocos casualizados com 15 tratamentos e quatro repetições, dispostos em esquema fatorial, 5 x 3, sendo cinco doses de N, na forma de uréia (0, 30, 80, 130 e 180 kg ha-1) e três sistemas de cobertura do solo (crotalária, milheto e o solo em pousio na entressafra). A quantidade de N nativo do solo absorvida pelo milho foi calculada pela diferença entre total de N acumulado na planta de milho, na época da maturação fisiológica, e o somatório do N proveniente da uréia, do milheto ou da crotalária determinados pelo método isotópico com 15N. O solo forneceu a maior quantidade de N para o milho, comparada à do fertilizante inorgânico conjuntamente à dos adubos verdes. As doses de N e os sistemas de cobertura do solo influenciaram significativamente a absorção de N nativo do solo pelo milho.

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The Curimataú estuary is located in the oriental coast of Rio Grande do Norte State in Brazil. Its importance resides in the fact that this region possesses one of the last portions of preserved mangrove in the Rio Grande do Norte State. Nevertheless, it has been severely affected by many anthropogenic activities, as sugarcane monoculture and shrimp farming. Former works demonstrated that an accumulation of heavy metals is occurring in oysters in this estuary, and perhaps it could be explained by the input of metals in this ecosystem deriving from the shrimp farming. To better understanding the origin of these metals, bottom sediment samples, cores and suspended particulate matter were collected for a characterization of metal concentrations (Al, Ba, Cd, Cu, Cr, Fe, Mn, Ni, Pb, Zn) and to determine the potentially bioavailable metals. Additionally, the enrichment ratio for each element analyzed was calculated. The mineralogical composition of sediment samples and cores were obtained by X-ray diffraction. Moreover, data of orbital remote sensing were used in order to detect and quantify suspended matter by applying a logarithmic algorithm. Geochemical data of bottom sediments and cores revealed that, excepting Ba and Pb, the elements analyzed presented concentrations characteristic of an unpolluted ecosystem (Al: 0,25 - 8,76 %; Ba: 3,03 - 870 µg.g-1; Cd: < 0,25 µg.g-1; Cr: 1,72 - 82,4 µg.g-1; Cu: 0,12 -25,3 µg.g-1; Pb: 0,38 - 23,7 µg.g-1; Fe: 0,10 - 5,82 %; Mn: 15,1 - 815 µg.g-1; Ni: 0,14 - 36,1 µg.g-1; Zn: 1,37 - 113 µg.g-1). During the dry season a distribution pattern was observed, with higher metal concentrations in the margins, decreasing toward the central portion of the channel. These metal concentrations were well correlated with mineralogical compositions, with clay minerals prevailing at the margins, and quartz and feldspar in the center. However, this pattern was not observed during the wet season, probably because of the high water flux that disturbed bottom sediments. But, as observed for the dry season, a good correlation between metal concentrations and mineralogical composition was also observed for the wet season, with high metal concentrations where there were high quantities of clay minerals. Low enrichment ratios were obtained for the majority of elements analyzed, excepting for Mn, Ba and Pb. Manganese presented the higher ratios downstream for both seasons, and it can be an evidence of anthropogenic impact by shrimp farming. As barium and lead concentrations in sediment samples presented analytical problems during the total sample digestion, one cannot be sure that the ratios obtained correspond to the reality. The highest metal concentrations in particulate matter were obtained in the portion dominated by fluvial transport for all metals analyzed, excepting for copper. Barium and zinc were the only elements that presented elevated concentrations that are not common of unpolluted ecosystems (Ba: 5730 - 8355 µg.g-1; Zn: 3899 - 4348 µg.g-1). However, these high concentrations could not be related to the shrimp farming and waste waters from the town of Canguaretama, once they were obtained from the fluvial particulate matter, that is upstream from the activities above mentioned. The application of the logarithmic algorithm to the processed LANDSAT image was well succeeded, although the acquired image does not correspond exactly to the field campaigns. The IKONOS image provided very detailed views of the suspended sediment concentration at the estuary, as the mixture of distinct water flows at the confluence of Cunhaú and Curimataú rivers, with more turbid waters from Cunhaú river, that is directly affected by effluents from shrimp farming and urban waste waters deriving from the town of Canguaretama

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Nowadays, as well as in the past decades, the dumping of biodegradable organic waste in landfill is common practice in Brazil, as well as in most parts of the world. Nevertheless due to its rapid decomposition and release of odors, this practice hamper’s the operation and implementation of a recycling system. These facts encouraged our research to find an efficient system for the management of organic waste, not only for the use of official workers responsible for managing these wastes, but also for non-governmental institutions. The Recycling for Life Community Association – ACREVI (Associação Comunitária Reciclando para a Vida), together with the municipal authorities of Mossoró-RN, Brazil, have assumed the social role of collecting and recycling solid waste produced by most of the local population. However, it was observed that the organic waste it collected was not receiving any treatment. This present work aims to make compost with mixed waste (green waste and organic household), and then do chemical analysis of the material in view to use the waste as organic fertilizer. The objective being: to share the knowledge acquired by putting it into a very simple language accessible to people with little education. The experiment was conducted at ACREVI, Mossoró (RN), and the compost was obtained following the method "windrow", forming three cells (I, II, III) with conical shape, dimensions of 1.6 meters and 2.0 meters in diameter for cells I and II, and 1.0 meters high and 2.0 meters in diameter for cell III. The process was accompanied by analysis: CHN elemental, a variation of cell temperature, humidity, pH, TKN, bulk density, nutrients and heavy metals. Stabilized organic compounds reached the C/N ratio of 10.4/1 cell I and 10.4/1 in the cell II in the cell, showing how good soil conditions, with potential to improve the physical properties of any soil and pH acid soils, has presented the cell III at the end of the process the C/N 26/1, is a high ratio may be associated with the stack size III, thus changing the optimal conditions for the occurrence of the process. The levels of heavy metals in the analyzed compounds were lower than those established by the SDA normative instruction, Nº 27, of 5 June, 2006. The use of pruning trees and grass are used in small-scale composting, while generating a quality compost in the final process, it also created an important condition for a correct sizing of the composting piles. Under the studied conditions it is not advisable to use cells with a height of 1.00 m in height and 2.00 m in diameter, as these do not prevent the rapid dissipation of heat and thus can not be a good product at the end of composting. The composting process in the shed of the association and the preparation of the primer enabled the development of an alternative technology to generate income for members of ACREVI.

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The study area is inserted in Ponta do Tubarão region, Macau City, setentrional littoral of Rio Grande do Norte State, composed of Tertiary and Quatemary sedimentary rocks and sediments. This region is characterized for the intense action of the coastal processes, causing the morphologic instability in part of the area, beyond the interference of human activities, as the Petroliferous Industrial Polo, salt companies and shrimp farms. This justifies the integration of multidisciplinary and multitemporal detailed scientific studies dealing with the evaluation of the changing behavior of this coastal environment by geoenvironments elements characterization, identifying protected and recuperation areas, mainly those under socioeconomic intervention. The main objective was the coastal monitoring using geoprocessing techniques to prepare thematic maps useful for oil spilling environment risk areas survey. The methodology was based on multitemporal interpretation of remote sensing images and field checking, integrated in a Geographical Information System (GIS). The Geologic, Geomorphologic, Vegetation, Soil and Land Use maps were prepared, and later on they allowed the generation of the Natural Vulnerability and Environmental Vulnerability maps. These maps had been classified in accordance with vulnerability degrees: very low, low, medi um, high and very high. Beyond these maps the GIS allowed the analysis of the shoreline evolution for 10 distinct dates, using Landsat 5 TM and 7 ETM+ and SPOT-HRVIR images. This analysis made possible the attendance of the coastal morphodynamic evolution, where the results had been represented by areasof erosion and accretion (or deposition) of sediments, pointing critical areas under erosive process to the petroliferous industry (Macau and Serra fields). The GIS also provided to prepare the Environmental Sensitivity Maps of Oil Spill (SAO Maps) in operational scale (1: 10.000), according to the norms ofthe Ministério do Meio Ambiente (MMA 2002). The SAO Map in operational scale was based on IKONOS images mosaic where the ESI (Environmental Sensitivity Index) was represented according with two tides phases of theregion. Therewere recognizedfiveESI (3, 4,7,9, 1O) for the low tide; to the high tide the ESI number increased to seven (3, 4, 5, 7, 8, 9, 10). All these information are necessary to the decisions making about oi! spill and its derivatives containment. These techniques application makes possible the optimization and implantation ofnew socioeconomics activities of low environmental impact, indicates areas for better productivity and security exploration, and benefits local communities with fauna and flora preservation. The development of these activities is inserted in the scope of Monitoramento Ambiental de Áreas de Risco a Derrames de Petróleo e Seus Derivados Cooperation Project (Rede 05/01 - PETRORISCO, FINEP/CTPETRO/PETROBRAS) of multidisciplinary and interinstitucional characteristics dealing with subjects involving the environmental monitoring and the petroliferous activity