310 resultados para Parcelas de monitoramento de erosão


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

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O objetivo deste trabalho foi testar o sistema de monitoramento computadorizado da produção de gás in vitro. Essa técnica facilita estudos da degradação das frações solúveis e insolúveis das forragens, quantificadas pela produção de gás (CO2 e CH4) oriunda do metabolismo microbiano e medida por sensor de pressão. Diversas quantidades de amostras (50 a 110 mg de feno de alfafa) e outros alimentos foram testadas. Também, a influência da quantidade de líquido ruminal (2,0 ou 3,0 mL), com ou sem barras magnéticas agitadoras nos frascos incubatórios, na digestibilidade de 100 mg de feno de alfafa, foi estudada. A quantidade de 100 mg de amostra, 2,0 mL de líquido ruminal e sem barra magnética agitadora, proporcionou os menores coeficientes de variação na produção de gás. em conclusão, 2,0 mL de líquido ruminal, sem barra e com 100 mg de amostra, apresentaram maior precisão na curva de digestão.

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RESUMO - O objetivo deste trabalho foi comparar o sistema de monitoramento computadorizado da produção de gás in vitro com os métodos in vivo e in situ. Nas comparações, foram utilizadas silagens de milho com alto/baixo teores de matéria seca, com/sem inoculante. A digestibilidade das silagens com alto teor de matéria seca (MS), com/sem inoculação, não apresentou diferenças entre os métodos analisados. Quando avaliadas separadamente do efeito do inóculo, essas silagens diferiram nos métodos in vitro/gás e in situ, mas não no in vivo. Entretanto, quando analisadas somente sob efeito do inoculante, apenas no método in situ houve diferença. Não foram encontradas diferenças na digestibilidade da fibra em detergente neutro (FDN) das silagens com alta ou baixa MS, inoculadas ou não, bem como em relação ao pH ao final da digestão. em conclusão, o desaparecimento da MS e FDN quantificada pelo resíduo no sistema in vitro/gás foi semelhante aos demais métodos avaliados.

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RESUMO - Os objetivos deste trabalho foram avaliar o sistema de monitoramento computadorizado da produção de gás in vitro e compará-lo com os métodos in vivo e in situ. Nos métodos de digestibilidade (MS), foram utilizadas amostras de silagens de milho com alto/baixo teor de MS, com/sem inoculante. Avaliando a digestibilidade das silagens, pelo gás produzido na fermentação, os resultados da extensão da degradação (A+D) foram: 21,5; 22,6; 22,1; e 20,9 mL de gás/100 mg MS, sem diferença significativa. Os coeficientes de determinação obtidos na produção de gás total, em relação ao potencial de degradação obtido in situ, mostraram-se elevados para silagem de milho com alta MS inoculada (R²= 0,99), alta MS não-inoculada (R²= 0,98), baixa MS inoculada (R²= 0,94) e baixa MS não-inoculada (R²=0,93). O desaparecimento da MS e/ou fibra em detergente neutro (FDN), quantificada pelo gás produzido no sistema in vitro/gás, apresentou resultados semelhantes aos demais métodos avaliados.

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Objective. To assess the potential for contamination of wastewaters from pig farming. Methods. Wastewaters from pig farming were stored in a tank. After 0, 30, 60, 90, and 120 days of hydraulic retention, they were added to lysimeters filled with argillaceous, sandy, or medium soil. Finally, these lysimeters were submitted to simulations of either a rainy season or a dry season. The number of colony-forming units (CFUs) of total coliforms, fecal coliforms, and fecal streptococci was measured in the effluents of the storage tank (for the various periods of hydraulic retention), in the percolate from the lysimeters, and in the three types of soil. The microbiological analyses were carried out using the membrane filter technique. The pH analyses were done potentiometrically. Results. For the three microorganisms, the largest decrease in bacterial counts in the storage tanks occurred with 90 or 120 days of retention. There was a marked decrease in the bacterial count in the percolates of the three soils. For the three soil types the greatest reduction in bacterial counts was found in medium soil, due to its acidity (pH < 7.0). Hydraulic retention was not sufficient to ensure the sanitary adequacy of the wastewaters and their use for irrigation, given that fecal coliform values were above 1 000 CFU per 100 mL. Therefore, adding the residues to the soil was considered a second stage of treatment. Conclusions. The retention of wastewaters followed by adding them to soil was effective in minimizing the contaminating effect of pig farming residues. The storage time for wastewaters from pig farming could be decreased from 120 to 90 days.

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The erosion caused by running water constitutes important cause of environmental degradation and productivity reduction, which justifies its evaluation in areas of eucalypt commercial plantations, mainly in ondulated slope conditions. The present study was intended to evaluate the influence of different management systems, in an undulated eucalypt pos-planting area, upon soil and water losses by erosion. The experiment was installed in a very clayey Red Latosol (Oxisol) under three eucalypt management systems (downhill planting with burning of crop residues - EDq; downhill planting with maintenance of crop residues on soil surface - ED; level planting with maintenance of crop residues on soil surface - EN), native forest (FN), bare soil (SD), and native pasture (PN). The soil and water losses evaluations were performed in standard plots installed in the field. All eucalypt systems presented very low values of soil losses in relation to the established tolerance limit, indicating the adequacy of these management systems concerning water erosion. The sustainability of these environments regarding erosion is indicated by the fact that soil losses in eucalipt were very close to those observed in native forest (reference).

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The objective of this work was to identify the spatial variability of the natural erosion potential, soil loss and erosion risk in two intensely cultivated areas, in order to assess the erosion occurrence patterns. The soil of the area located at Monte Alto, São Paulo state, was classified as Paleudalf (PVA) with moderately slope, with different managements. The soil of the area located at Jaboticabal, São Paulo state, was classified as Haplortox(LV) with gentle slope and cultivated with sugarcane. A irregular grid was imposed on the experimental areas. Soil samples were obtained from 0-0.2 m depth at each grid point: 88 samples in Monte Alto area (1465 ha) and 128 samples at Jaboticabal area (2597 ha). In order to obtain the values of the studied variables USLE was applied at each grid point. Descriptive statistics were calculated, and geoestatistical analyses were performed for defining semivariograms. Kriging techniques to develop map showing spatial patterns in variability of selected soil attributes were used. All variables showed spatial dependence. The PVA soil showed higher erosion risk due to the slope and atual management compared to the soil LV.

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This study aimed at the elaboration of a database with information and a map of erosion vulnerability for ecological zoning for the upper Pardo River, Botucatu, SP, by using the Geographical Information System - SPRING. The map of erosion vulnerability was made from spectrally homogeneous regions, producing a grid of zone averages, which was then subdivided, resulting in a vulnerability map to erosion. The results allowed us to conclude that digital imaging produced valuable information for mapping of soil use and database formation. The GIS - SPRING was efficient at identifying soil and vulnerability erosion classes and 95% of the basin presents a moderately stable vulnerability degree, through the presence of medium young soils in gently waring reliefs and covered by 49.27% of pasture and 29.88% crops.

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Accelerated soil erosion is, at present, one of the most widespread environmental problems in the world. Geographic Information Systems (GIS) have become an essential tool in soil erosion studies and consequently in the development of appropriate soil conservation strategies. The objective of this paper was to assess the degree of soil erosion associated with land cover dynamics through GIS analysis and to validate the modeling with indicators of soil erosion. Universal Soil Loss Equation (USLE) model, GIS technology and ground-truth dataset (erosion indicators) were employed to elaborate the soil loss maps for four dates at Sorocaba Municipality (SP, Brazil). It was verified that, although the predicted soil loss rate is normally small along the study area, such rate is significantly greater than the soil formation rate. This shows a non-sustainable situation of soil and land cover management. Unplanned urban expansion seems be the main driving force that acts in increasing the erosion risk/occurrence along the study area.

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The agricultural unpaved roads are important road structures for the economic and social agricultural development of the Nation, and the erosion provoked by rain water in the road bed and sides are closely related to bad draining, one of the main factors for their degradation. In order to make the draining system adequate, it is necessary to know about erodibility, infiltration capacity of water in the ground and adoption of mechanical slope abatement with grid elevation and water interception. This study presents drainage model through the construction of terraces with gradient transversally associated to the capitation basin in abruptic red dystrophic argisol soils, medium sandy texture, based on slops abatement techniques, elevating the road bed and deviating flow. The grain sized fractions of this ground (sand, silt, clay) and the aggregate stability indicated that this ground, under anthropic action, presents erosive processes resulting in superficial draining with ground hauling, sanding sources and courses of water situation below roads, providing great environmental impacts in the hydric bodies. The reduction of erosion problems in these unpaved roads is in the adoption of measures that intercept waters from the draining of their stream bed itself, as well as pluvial waters comings from adjacent areas of contribution, that are collected and conducted to inlaid terraces and capitation basis.

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The objective of this work was to verify the application of cluster analysis to evaluate soil erosion risk for different soil classes, soil slopes and soil managements. The study was conducted in a 33 ha section of a large field located in Carmo do Rio Claro County, MG, Brazil. The field had been managed in a corn/bean rotation under conventional tillage and under coffee plantation for seven years, both under sprinkle irrigation. Soil samples were obtained at every 10 m at 0.20 m depth along a transect of 1050 m. Soil erosion risk (A), natural potential erosion (PN), and erosion expectation (EE) were determined and submitted to a cluster and principal component analysis. The application of clustering analysis showed high correlation between the clusters and soil types. With clustering analysis plus principal components analysis, it was possible to identify groups of high and low soil erosion expectation, showing that the areas with higher soil erosion expectation are correlated to the soil class, soil slope and soil management. Among the studied variables, the natural potential erosion (PN) showed to be the most important factor to identify different soil erosion groups. The cluster analysis showed that 98% of the variables were classified within each group, and that they should be managed differently due to the soil erosive potential of each group,.

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The highways are enterprises of great longitudinal extension that cross several types of lands, that possess different geologic, geomorphologic, pedologic and vegetation conditions. In the environmental management of highways the importance of the use of Engineering Geological Maps of Susceptibility was noticed, for being documents that inter-relates several information of the environment. This way, this research objectified the elaboration of this type of map and the indication of lines of direction for the conservation of the Highway Marechal Rondon - SP-300. For its elaboration the Map of Declivity, the delimited Homogeneous Physiographic Units, the processes of the superficial dynamics mapped and the use of the ground was used. Its elaboration evidenced its importance for the environmental management of highways, in view of the prevention, the monitoring and the correction of the adverse processes that can occur in this type of enterprise.

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Monitoring the survival of nematophagous fungi is needed to establish periods of reapplication of formulations of nematophagous fungi to control the citrus nematode in the field. We monitored the survival of fungi: Arthrobotrys robusta, A. oligospora, A. musiformis Dactylella leptospora and Monacrosporium eudermatum in plots treated with 1, 2, 4, 6 liters of the formulation of fungi/plant or witness without the application, during the period of nine months with the first assessment six months after application and the other with intervals of three months after the first evaluation. The fungus D. leptospora was found only in the evaluation of 6 months after treatment application, indicated a short survival time in the soil. However, the isolated A. robusta, A. musiformis and A. oligospora were recovered in all evaluations and especially in plots treated with higher doses of the formulation and witness. Monacrosporium eudermatum was recovered in all experimental periods and even in assessing the witness portion of nine months after application. The fact of the presence of species of Arthrobotrys and M. eudermatum in control plots indicates that native species that were already orchard.

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Brazil has great potential of water resources, however, with deficiency in terms of qualitative and quantitative monitoring and knowledge of the influences of land use. So, this study had the purpose of presenting the qualitative and quantitative monitoring of water for irrigation and the influences caused by the use and occupation of land in the watershed of Ipê stream, in the municipality of Ilha Solteira, São Paulo. The qualitative monitoring was conducted from 2006 to 2011 and the quantitative monitoring from 2009 to 2011. In order to evaluate the influences, the Pearson correlation analysis was used. It was found that the watershed is mostly made up by the crop of sugar cane and the use in conflict with areas of permanent preservation are the fallow areas and pasture. The watershed is characterized with high concentrations of iron and coliforms, originating from degraded pastures and irregular use of urban and rural occupation. The small permanent preservation areas, bad soil conservation and expansion of urban areas imply in the deterioration of the quality and availability of water, generating socio-economic and environmental impact in the area.

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Several factors have contributed to the increase the world production of urban solid waste, resulting in difficulties to the correct management and the final environmentally appropriate disposal, in addition to causing serious socio-economic, environmental, and public health troubles. The soil and groundwater contamination by leachate in waste disposal sites is almost always present, leveraging the emergence and/or adaptation of methodologies for environmental assessment of these areas. The geophysical methods, especially the electrical resistivity method, are fast, reliable and low-cost alternative for this purpose. This paper reports the methodology adopted for the temporal monitoring of the plume of contamination of controlled landfill in the municipality of Rio Claro (SP). Electrical resistivity data were obtained in 1999 and 2008, by the resistivity method, using the techniques of vertical electrical sounding and electrical profile. In both years, similar tests were carried out in the same locations within the disposal area. The results indicated that the plume of contamination has resistivity values less than or equal to 50 ohm.m and moves guided by 2 flows: the main, to the southeast, and the secondary, to the west. Relatively to the first series of tests in 1999, the plume of contamination was higher and deeper in 2008, contrary to what was expected for a landfill deactivated for at least 10 years.