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| Registros recuperados: 46 | |
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| Oliveira,Sonia M.B. de; Pessenda,Luiz C.R.; Gouveia,Suzy E.M.; Favaro,Deborah I.T.. |
| This paper examines the role of parent rock, pedogenetic processes and airborne pollution in heavy metal accumulation in soils from a remote oceanic island, Fernando de Noronha, Brazil. We studied five soil profiles developed from different volcanic rocks. Mineralogical composition and total concentrations of major and trace elements were determined in 43 samples. The obtained concentrations range for heavy metals were: Co: 26-261 ppm; Cu: 35-97 ppm; Cr: 350-1446 ppm; Ni: 114-691 ppm; Zn: 101-374 ppm; Hg: 2-150 ppb. The composition of soils is strongly affected by the geochemical character of the parent rock. Pedogenesis appears to be responsible for the accumulation of Zn, Co, and, to a lesser extent, of Ni and Cu, in the upper, Mn- and organic... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Heavy metals; Soils; Anthropogenic mercury; Fernando de Noronha. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652011000400007 |
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| Becegato,Valter Antonio; Ferreira,Francisco José Fonseca; Machado,William César Pollonio. |
| Gamma spectrometric measurements were obtained for the agricultural soils aiming at characterizing the spatial distribution of radionuclide concentrations (K, eU and eTh), as well for the samples of phosphatic fertilizers and agricultural gypsum. In the study areas, three types of soils occured: Eutrophic Red Nitosol (Alfisoil), Eutroferric Red Latosol of clayey texture (Oxisoil) and Dystrophic Red Latosol of medium texture (Oxisoil). The results showed that the radionuclide concentrations in more clayey soils were higher than in more sandy soils, mainly as a function of a higher adsorption capacity of the former. For the area where human activity predominated, the average contents of K, eU and eTh were respectively 54.75; 10.22 and 7.27 Bq/Kg,... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Gamma-rays spectrometry; Soils; Fertilizers. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132008000600022 |
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| Cruz,Lútecia Hiera da; Santana,Henrique de; Zaia,Cássia Thaïs Bussamra Vieira; Zaia,Dimas Augusto Morozin. |
| This work showed that the adsorption of glyphosate (GPS) depends on surface area for clays and amount of clays and CEC for soils. Organic matter (OM) had a secondary role in the adsorption of GPS on soils. The adsorption of GPS on soils from Londrina and Floraí counties and clays (montmorillonite, kaolinite) decreased when pH increased, however, for bentonite clay and soil from Tibagi county was kept constant. For the soils, the competitive adsorption between GPS and phosphate showed that displace of GPS by phosphate was related to the amount of clays, CEC and pH. GPS was not easily displaced by phosphate on the clays. The FT-IR spectra of the soils and clays showed that soil from Londrina resembled kaolinite. Thus, this could explain the results of... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Glyphosate; Adsorption; Clays; Soils. |
| Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132007000300004 |
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| Becegato,Valter Antonio; Ferreira,Francisco José Fonseca; Cabral,João Batista Pereira; Rafaelli Neto,Sílvio Luis. |
| In this study the K, U and Th radionuclide concentrations were determined in a sugar cane plantation that received large quantities of fertilizer and gypsum. Geochemical data were obtained for the clay, iron and organic matter in the soil samples, taken from depths of 0-20 and 20-40 cm. The average radionuclide concentrations were 71 Bq Kg-1 for K; 5.97 Bq Kg-1 for U, and 11.26 Bq Kg-1 for Th, and the uranium was variable (56%). The radionuclide average concentrations for the different fertilizer compositions varied in the range of 603.5 - 8855.0 Bq Kg-1 for K; 27.3 - 684.4 Bq Kg-1 for U, and 58 - 788.5 Bq Kg-1 for Th, and it was most variable for K (53%). Gypsum average concentrations were 82.6 Bq Kg-1 for K, 641.5 Bq Kg-1 for U, and 201.7 Bq Kg-1 for Th,... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Fertilizers; Soils; Radionuclides; Gamma-ray spectrometry. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132008000100001 |
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| Registros recuperados: 46 | |
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