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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

G?nese de ?Latossolos Acinzentados? em topossequ?ncia deLatossolos das chapadas do Alto Vale do Jequitinhonha,MG. / Genesis of Xanthic Haplustox in toposequence of Oxisol tableland of the Alto Vale do Jequitinhonha, MG.

Ferreira, Celmo Aparecido 31 July 2008 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-27T15:42:49Z No. of bitstreams: 5 10.pdf: 2690869 bytes, checksum: 0e823732493249059e143a237bd69321 (MD5) license_url: 49 bytes, checksum: fd26723f8d7edacdb29e3f03465c3b03 (MD5) license_text: 20626 bytes, checksum: 7851d446050a985bd0603b7c4cee472d (MD5) license_rdf: 19710 bytes, checksum: aa65da15f424ff71c620a992a187295c (MD5) license.txt: 2109 bytes, checksum: aa477231e840f304454a16eb85a9235f (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-27T18:16:18Z (GMT) No. of bitstreams: 5 10.pdf: 2690869 bytes, checksum: 0e823732493249059e143a237bd69321 (MD5) license_url: 49 bytes, checksum: fd26723f8d7edacdb29e3f03465c3b03 (MD5) license_text: 20626 bytes, checksum: 7851d446050a985bd0603b7c4cee472d (MD5) license_rdf: 19710 bytes, checksum: aa65da15f424ff71c620a992a187295c (MD5) license.txt: 2109 bytes, checksum: aa477231e840f304454a16eb85a9235f (MD5) / Made available in DSpace on 2015-02-27T18:16:18Z (GMT). No. of bitstreams: 5 10.pdf: 2690869 bytes, checksum: 0e823732493249059e143a237bd69321 (MD5) license_url: 49 bytes, checksum: fd26723f8d7edacdb29e3f03465c3b03 (MD5) license_text: 20626 bytes, checksum: 7851d446050a985bd0603b7c4cee472d (MD5) license_rdf: 19710 bytes, checksum: aa65da15f424ff71c620a992a187295c (MD5) license.txt: 2109 bytes, checksum: aa477231e840f304454a16eb85a9235f (MD5) Previous issue date: 2008 / O Sistema Brasileiro de Classifica??o de Solos (SiBCS) ? um sistema taxon?mico, aberto e que se encontra em constru??o permanente, conforme novos conhecimentos sobre solos brasileiros s?o obtidos. O objetivo deste trabalho foi efetuar a caracteriza??o qu?mica, f?sica, morfol?gica, micromorfol?gica e mineral?gica de um ?Latossolo Acinzentado? (?LAC?) em topossequ?ncia formada por Latossolos representativos dos solos das chapadas da regi?o do Alto Vale do Jequitinhonha-MG, enfatizando aspectos de sua g?nese e contribuir para a cria??o da subordem ?LAC? no SiBCS. A topossequ?ncia localizada no munic?pio de Itamarandiba, MG, est? inserida no Planalto do Jequitinhonha, em ?reas denominadas chapadas, elaboradas sobre rochas do Grupo Maca?bas, com clima Aw segundo classifica??o de Koppen. A vegeta??o nativa ? o Cerrado, no entanto, na ?rea estudada predomina o reflorestamento com Eucaliptus spp. Os perfis ocupam as seguintes posi??es da vertente: topo (P18) ? Latossolo Vermelho, ter?o m?dio de vertente (P25) ? Latossolo Vermelho-Amarelo, ter?o inferior de vertente (P19) ? Latossolo Amarelo e sop? (P20) ? ?LAC?. Estes perfis foram descritos e amostrados para caracteriza??o proposta. Foram realizadas an?lises qu?micas e f?sicas de rotina. Os teores totais de Fe, Ti, Al, Mn e Si foram determinados pelo ataque sulf?rico e os ?xidos de Fe, Al e Mn foram avaliados nos extratos de ditionito-citrato-bicarnonato e oxalato. A mineralogia foi identificada pela difratometria de raios-X e os ?xidos de Fe foram identificados pela difratometria diferencial de raios-X. Por espectrometria de fluoresc?ncia de raios-X foram determinados Ti, Ga e Zr.Todos os solos apresentaram atributos morfol?gicos, f?sicos, qu?micos e mineral?gicos t?picos da classe dos Latossolos. P20 apresentou cores acinzentadas, significativos fragmentos de estrutura maci?a, caracter?stica de Gleissolos, nos horizontes A e BA. Todos os perfis s?o muito argilosos, distr?ficos, com baixos teores de P dispon?vel e pH em torno de 5. Os ?xidos de Fe, de modo geral, refletiram a cor dos solos e diminu?ram ao longo da vertente. A diminui??o de Fe cristalino e de baixa cristalinidade ao longo da vertente confirmou a perda de Fe. O Si seguiu o caminho inverso e o Al total permaneceu constante. A diminui??o da rela??o Fe2O3/TiO2 em P20 indicou problemas de drenagem neste solo. A mineralogia da fra??o argila em todos os perfis ? dominada por caulinita e gibbsita. Em P18 foram identificados hematita e goethita, em P25 hematita com baixa intensidade e goethita, em P19 goethita e em P20 n?o foram identificados ?xidos de Fe. A micromorfologia mostrou a predomin?ncia da microestrutura granular e porosidade do tipo empilhamento complexo, t?picos de Latossolos, em P18, P25 e P19. Em P20 cerca de 25% da ?rea da l?mina do horizonte A/BA ? composto pela microestrutura maci?a de colora??o cinza e 45% ? formada por microestrutura tipo microgranular, sendo esta, predominante Bw. A forma??o dos Latossolos da topossequ?ncia estudada pode estar relacionada com a evolu??o da rede de drenagem e pela a??o da fauna a latossoliza??o predominou na forma??o do ?LAC?. Os atributos dos solos da topossequ?ncia convergem para uma ?nica classe de solo, a dos Latossolos, que s?o originados do mesmo material de origem. O ?LAC? apresentou todos os atributos necess?rios ao seu enquadramento na classe dos Latossolos, exceto as cores acinzentadas. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Produ??o Vegetal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2008. / ABSTRACT The Brazilian System of Soils Classification (SiBCS) it is a s taxonomic system, open and that meets in permanent construction, as new knowledge on Brazilian soils are obtained. The objective of this work went characterize morphologically, micromorphologically, chemically, physically and mineralogically a Xanthic Haplustox (?LAC?) in toposequence formed by representative Oxisol of the soils of the tableland occupying most of the land agricultural the region of the Alto Vale do Jequitinhonha, MG, emphasizing aspects of its genesis and to contribute to the creation of the suborder ?LAC? in SiBCS. The toposequence located in the municipality of Itamarandiba, MG, is inserted in the Jequitinhonha Plateau, in areas known as tableland, elaborated on rocks of the Maca?bas Group, with climate Aw second Koppen classification.The native vegetation is the Cerrado, however, in the area in study the reforestation prevails with Eucaliptus spp. The profiles occupy the following positions of the slope: top (P18) - Rhodic Haplustox, medium third (P25) - Typic Haplustox, lower third (P19) - Typic Haplustox and foot slope (P20) - "LAC". These profiles were described and collected to carry out the characterization proposal. The chemical and physical analyses of routine were accomplished. The total amount of Fe, Ti, Al, Mn and Si was determined for the attack sulfuric and the Fe oxides, Al and Mn were appraised in the dithionite-citrate-bicarbonate extracts and oxalate. The mineralogy was identified by the x-ray diffraction and the Fe oxides were identified for the differential x-ray diffraction. For fluorescence spectrometry X-ray they were certain Ti, Ga e Zr. All the soils presented morphological, physical, chemical and mineralogical typical attributes of the class Oxisol. P20 presented gray color, fragments of massive structure significant, characteristic of Entisol in horizons A and BA. All profiles are clay, distrophic, with low levels of available P and pH around 5. The Fe oxides, in general, reflected the color of the soil and decreased along the slope. The decrease of crystalline Fe and low crystallinity along the slope confirmed the loss of Fe. The Si followed the other way and Al total remained constant. The decrease of relationship Fe2O3/TiO2 indicated in P20 drainage problems in this soil. The mineralogy of clay in all the profiles it is dominated by kaolinite and gibbsite. In P18 were identified hematite and goethite, in P25 hematite with low intensity and goethite, in P19 goethite and in P20 were not identified Fe oxides. The micromorphology showed the prevalence of granular microstructure and packing voids, typical of Oxisol, P18, P25 and P19. In P20 about 25% of the area of the blade the horizon A/BA is composed of the massive microstructure of gray color and 45% is formed by granular microstructure, being this, Bw predominant. The formation of Oxisol of the studied toposequence it can be related with the evolution of the drainage net and for action of the fauna the feralitization prevailed in the formation of " LAC ". The attributes of soil toposequence converge to a single class of soil, the Oxisol, which originated from the same parent material. The ?LAC? had all the attributes necessary for to be included in the class of Oxisol, except the color gray.

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