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| Carmo,Danilo Almeida Baldo do; Marques Júnior,José; Siqueira,Diego Silva; Bahia,Angélica Santos Rabelo de Souza; Santos,Henrique Menezes; Pollo,Gustavo Zanetti. |
| Resumo O objetivo deste trabalho foi verificar a eficácia da cor do solo na identificação de áreas com diferentes potenciais produtivos e qualidade de café, em Argissolo Vermelho-Amarelo desenvolvido de arenito, no Planalto Ocidental Paulista, no Estado de São Paulo. Coletaram-se 173 amostras em 39 ha, para a determinação de matiz, valor, croma e índice de avermelhamento do solo, com base nos dados da espectroscopia de reflectância difusa (ERD). Avaliaram-se, também, a produtividade e a qualidade do fruto de café, e calculou-se o índice de diagnose foliar (DRIS). A maior correlação espacial observada pelo variograma cruzado ocorreu entre matiz e DRIS, em pontos distantes em até 497 m. A menor correlação espacial foi observada em croma e produção, em pontos... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Coffea arabica; Cor do solo; Geoestatística; Pedometria. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2016000901261 |
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| Fernandes,Kathleen Lourenço; Ribon,Adriana Aparecida; Marques Junior,José; Bahia,Angélica Santos Rabelo de Souza; Tavares Filho,João. |
| Abstract: The objective of this work was to estimate the iron oxide contents (hematite and goethite) and to characterize the color and the spectral and magnetic signatures of Cerrado soils in the state of Goiás, Brazil. Six Oxisols and one Inceptisol were studied. Spectral and magnetic signatures were determined by diffuse reflectance spectroscopy (DRS) and magnetic susceptibility, respectively. Then, the spectral curves and the second derivative calculations were used to determine hematite and goethite contents, as well as soil color after conversion into tristimulus values. Hematite and goethite contents were also obtained by x-ray diffractometry, and soil color was also defined in the field (Munsell color chart). The values for the isomorphic... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Diffuse reflectance spectroscopy; Goethite; Hematite; Magnetic susceptibility; Oxisols. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2017001000923 |
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| Bahia,Angélica Santos Rabelo de Souza; Marques Júnior,José; Panosso,Alan Rodrigo; Camargo,Livia Arantes; Siqueira,Diego Silva; Teixeira,Daniel De Bortoli; Scala Júnior,Newton La. |
| Soil CO2 emission (FCO2) is one of the main sources of carbon release into the atmosphere. Moreover, FCO2 is related to soil attributes governing the transfer of gases from soil to the atmosphere. This study aimed firstly to describe the spatial variability of hematite (Hm), goethite (Gt), iron extracted with sodium dithionite-citrate-bicarbonate (Fed) contents, soil CO2 emission (FCO2) and free-water porosity (FWP) and secondly, to develop statistical models to predict the above mentioned factors in an Oxisol cultivated under manual harvesting of sugarcane (Saccharumspp.) in southeastern Brazil. The study was conducted on an irregular 50 m × 50 m grid containing 89 points, each 0.5-10 m apart. The 0-0.1 m soil layer at each sampling point was used to... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Hematite; Goethite; Soil respiration; Geostatistics; Cross-semivariograms. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162015000200157 |
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