Ao exigir áreas de Preservação Permanente (APP) e Reserva Legal (RL) em todos os imóveis rurais do Brasil, o Código Florestal Brasileiro (Lei Federal 4771/1965) se reverte em um dos instrumentos mais importantes com o propósito de mitigar impactos ambientais das atividades agrícolas. Como em outros estados, no Paraná esta legislação também foi ignorada; para cumprir o disposto no Código Florestal e estipular prazo para as adequações necessárias, foi instituído o Sistema de Manutenção, Recuperação e Proteção da Reserva Legal e Áreas de Preservação Permanente - SISLEG (Decreto Estadual 387/1999). Com o objetivo de se analisar essas normativas, elaborou-se um estudo de imóvel rural típico dos Campos Gerais do Paraná e, com base em técnicas de sensoriamento remoto, se definiram as APPs e o montante necessário para compor a RL. Como a legislação não especifica critérios objetivos para a localização das RLs, duas perspectivas foram avaliadas: a maximização do potencial agrícola da propriedade e a conservação da natureza, com base no contexto ambiental e hidrográfico no qual o imóvel está inserido. Conclui-se que a legislação pode contribuir para mitigar impactos não contemplando, porém, conceitos importantes para o planejamento territorial e conservação da natureza.
ABSTRACT:With the rise of restrictions imposed by law for gases emission, several technologies both for petrodiesel (PD) or diesel engines are been applied, such as the sulfur reduction and the injection electronic command, followed of gases recirculation and/or after-treatment. The utilization of biofuels is considered as an interesting option for pollutants reduction. In this study was evaluated the performance on short duration tests (minor period than the factory indication of the lubricant lifespan) of the Diesel engine fueled with four vegetable oils. With the aim to select the most interesting oils for future evaluations in long duration tests. The analyzed variables were fuel consumption, power relative loss and opacity, for oils of linseed, crambe, rapseed, jatropha , with 100 °C preheating and engine work temperature (60 °C) comparing those with the PD. It was verified that the vegetable oils, on average, present a lower consumption than the PD for the cases of working without load, however with load, they presented higher consumption. In addiction were observed that the oils show a higher relative power loss in relation of PD and provides lower emission of particulate matter. Crambe and canola presented the best performance among the evaluated oils.
Brazil is doing a major effort to find alternatives to diesel oil as combustible. Some study lines are oriented to the development of vegetable oils used as fuel, as a source of getting cheaper and have higher energy density than the converted vegetable oils, and less risk of environmental contamination. The aim of this study was to evaluate the performance, the useful life of the lubricant and some components of a Diesel Cycle engine, with an electronic injection system, in a long-term test operating with a preheated blend (65°C) of 50% (v v -1 ) of soybean oil in petrodiesel. There was a reduction of the useful life of the injectors which presented failure because of high wear with 264 hours of operation and showed an increase in emissions of particulate matter (opacity) which may be assigned to the failures occurred in the injection system. An increase in the useful life of the lubricant, when compared with the literature was also observed. The electronic injection system may favor the burning of the tested fuel. The test was interrupted with 264 hours because of failures in the injection system.
ABSTRACT:The study of spatial variability of soil and plants attributes, or precision agriculture, a technique that aims the rational use of natural resources, is expanding commercially in Brazil. Nevertheless, there is a lack of mathematical analysis that supports the correlation of these independent variables and their interactions with the productivity, identifying scientific standards technologically applicable. The aim of this study was to identify patterns of soil variability according to the eleven physical and seven chemical indicators in an agricultural area. It was used two multivariate techniques: the hierarchical cluster analysis (HCA) and the principal component analysis (PCA). According to the HCA, the area was divided into five management zones: zone 1 with 2.87ha, zone 2 with 0.8ha, zone 3 with 1.84ha, zone 4 with 1.33ha and zone 5 with 2.76ha. By the PCA, it was identified the most important variables within each zone: V% for the zone 1, CTC in the zone 2, levels of H+Al in the zone 4 and sand content and altitude in the zone 5. The zone 3 was classified as an intermediate zone with characteristics of all others. According to the results it is concluded that it is possible to separate into groups (management zones) samples with the same patterns of variability by the multivariate statistical techniques.KEYWORDS: multivariate analysis, precision agriculture, spatial variability. ZONAS DE MANEJO AGRÍCOLAS DE ACORDO COM VARIÁVEIS DE SOLO E PAISAGEM RESUMO:O estudo da variabilidade espacial de atributos do solo e plantas ou agricultura de precisão, técnica que visa ao uso racional dos recursos naturais, está expandindo-se comercialmente no Brasil. Porém ainda ressente-se de análise que dê respaldo matemático a correlação de variáveis independentes e suas interações com a variável produtividade, identificando padrões científicos tecnologicamente aplicáveis. Objetivou-se identificar padrões de variabilidade do solo com base em onze indicadores químicos e sete físicos em área agrícola. Utilizaram-se duas técnicas de estatística multivariada: análise hierárquica de agrupamentos (HCA) e análise por componentes principais (PCA). De acordo com a HCA, separou-se a área de estudo em cinco zonas de manejo, sendo a zona 1 com 2,87 ha; a zona 2 com 0,8 ha; a zona 3 com 1,84 ha; a zona 4 com 1,33 ha; e a zona 5 com 2,76ha. Por meio da PCA identificaram-se as variáveis mais importantes dentro de cada zona: na zona 1 o V%; na 2 a CTC; na 4 o H+Al, e na 5 o conteúdo de areia e a altitude. A zona 3 foi classificada como uma zona intermediária, apresentando características de todas as outras. Sendo assim, é possível separar em grupos (zonas de manejo) as amostras que possuem os mesmos padrões de variabilidade com técnicas de estatística multivariada.
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