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Almeida,Ronaldo de; Bernardi,José Vicente Elias; Oliveira,Ronaldo Cavalcante; Carvalho,Dario Pires de; Manzatto,Angelo Gilberto; Lacerda,Luiz Drude de; Bastos,Wanderley Rodrigues. |
The study was conducted in Puruzinho lake (Humaitá, AM) considering seasonal periods of rainy and dry in way to elucidate the flood pulse importance in the deposition, remobilization and distributions of mercury and organic matter in bottom sediments in the Madeira River Basin (Brazilian Amazon). Bottom sediments and soils samples were analyzed for total mercury and organic matter. Mercury concentrations obtained in bottom sediment were 32.20-146.40 ng g-1 and organic matter values were 3.5 - 18.0%. The main region for accumulation of mercury and organic matter was in the central and deepest lake area In the rainy season there was a greater distribution of Hg and organic matter, mainly controlled by means of income of the Madeira river water during... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Organic matter; Indicator kriging; Madeira river; Seasonality. |
Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0044-59672014000100010 |
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Bonnin,Juan José; Mirás-Avalos,José Manuel; Lanças,Kléber Pereira; González,Antonio Paz; Vieira,Sidney Rosa. |
The aim of this work was to analyze the spatial distribution of soil compaction and the influence of soil water content on the resistance to penetration. The latter variable was described by the cone index. The soil at the study site was a Nitisol and the cone index data were obtained using a penetrometer. Soil resistance was assessed at 5 different depths, i.e. 0-10 cm, 10-20 cm, 20-30 cm, 30-40 cm and deeper than 40 cm, whereas soil water content was measured at 0-20 cm and 20-40 cm. Soil water conditions varied during the different samplings. Coefficients of variation for cone index ranged from 16.5% to 45.8% while those for soil water content varied from 8.96% to 21.38%. Results suggested a high correlation between soil resistance, as assessed by the... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cone index; Indicator kriging; Soil compaction; Spatial distribution. |
Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052010000500017 |
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Mendonça,Patrícia Gabarra; Teixeira,Daniel De Bortoli; Moitinho,Mara Regina; Silva Junior,João Fernandes da; Oliveira,Ismênia Ribeiro de; Martins Filho,Marcílio Vieira; Marques Junior,José; Pereira,Gener Tadeu. |
ABSTRACT The identification of erosion-susceptible areas is fundamental for the adoption of soil conservation practices. Thus, the best way to estimate the spatial pattern of soil erosion must be identified, in which the process uncertainties are also taken into consideration. The purpose of this study was to evaluate the spatial and temporal uncertainty of soil loss under two scenarios of sugarcane harvest management: green cane (GC) and burnt cane (BC). The study was carried out on a 200-ha area, in Tabapuã, São Paulo State, Brazil. A regular 626-point sampling grid was established in the area, with equidistant intervals of 50 m and a final plant density of about 3.3 samples per ha. The probability that the soil loss would exceed the tolerable limit of... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Green cane; Burnt cane; Geostatistics; Indicator kriging. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832018000100512 |
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Grego,Célia Regina; Vieira,Sidney Rosa; Lourenção,André Luiz. |
The knowledge of the spatial distribution of insect populations in crops allows the estimation of the population density in space, the classification of damage impact on yield as well as decisions to be made about control measures. To evaluate the spatial distribution of the wheat armyworm Pseudaletia sequax Franclemont, in relation to the development and yield of triticale (Triticum secale Wittmack) under no-till management, samplings were taken at 302 points in a square grid measuring 10 x 10 m, in Campinas, SP, Brazil. The caterpillar population was evaluated by counting their number per meter at the base of triticale plants. Grain yield (kg ha-1), cover of the above-ground part (kg ha-1), mean plant height (m), and ground cover percentage were... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Triticum secale Wittmack; Insecta; Wheat armyworm; Geostatistics; Indicator kriging. |
Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162006000400002 |
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