Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2016-01-05T13:15:52Z No. of bitstreams: 2 roberto_vial_costa.pdf: 15489800 bytes, checksum: 9f9751662053d8d2274f3f49ba3836c5 (MD5) license_rdf: 22974 bytes, checksum: 99c771d9f0b9c46790009b9874d49253 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2016-01-05T17:54:58Z (GMT) No. of bitstreams: 2 roberto_vial_costa.pdf: 15489800 bytes, checksum: 9f9751662053d8d2274f3f49ba3836c5 (MD5) license_rdf: 22974 bytes, checksum: 99c771d9f0b9c46790009b9874d49253 (MD5) / Made available in DSpace on 2016-01-05T17:54:58Z (GMT). No. of bitstreams: 2 roberto_vial_costa.pdf: 15489800 bytes, checksum: 9f9751662053d8d2274f3f49ba3836c5 (MD5) license_rdf: 22974 bytes, checksum: 99c771d9f0b9c46790009b9874d49253 (MD5) Previous issue date: 2014 / Os ?xidos de ferro s?o indicadores de fatores pedogen?ticos, incluindo a litologia dominante no material de origem, e revelam caracter?sticas pedo-ambientais diagn?sticas, inclusive, como base para o agrupamento hier?rquico, e, em muitas circunst?ncias, da potencialidade agr?cola dos solos, sobretudo os de ?reas tropicais do globo. Solos magn?ticos s?o aqueles que apresentam altos teores totais de ?xidos de ferro e elevada magnetiza??o espont?nea. S?o produtos do intemperismo de rochas b?sicas e apresentam atributos qu?micos e f?sicos que permitem sua explora??o (ou uso) agr?cola tanto para subsist?ncia como para fins comerciais. Na Serra do Espinha?o Meridional - SdEM e no Alto Vale do Jequitinhonha ? AVJ , os solos magn?ticos s?o originados de gabros e de xistos verdes. O presente trabalho teve como objetivo caracterizar morfologicamente, quimicamente, fisicamente, mineralogicamente e qu?mico-estruturalmente sete solos magn?ticos e do AVJ e SdEM. Foram descritos no campo, amostrados e classificados os seguintes solos: Latossolo Vermelho Distr?fico t?pico ? LVd1 (Couto de Magalh?es), Nitossolo Vermelho Distrof?rrico t?pico ? NVdf (Planalto de Minas), Latossolo Vermelho Distr?fico t?pico ? LVd2 (Turmalina), Latossolo Vermelho Distrof?rrico t?pico ? LVdf (Pinheiro), Latossolo Vermelho Distr?fico t?pico ? LVd3 (Serra Azul de Minas), Latossolo Vermelho Distr?fico t?pico ? LVd4 (Pedro Lessa) e Chernossolo Argil?vico ?rtico saprolitico ? MTo (Carbonita/Estiva de Cima). Foram realizadas an?lises qu?micas, an?lise granulom?trica, an?lise mineral?gica por difratometria de raios-X, microscopia eletr?nica de varredura e espectroscopia de energia dispersiva e espectroscopia M?ssbauer. Determinou-se o teor total de ?xidos de Fe, Al, Ti, Mn e Si por meio do ataque sulf?rico e calculou-se as rela??es molares Ki e Kr. Os resultados evidenciam diferen?as marcantes entre os atributos f?sicos, qu?micos, morfol?gicos e mineral?gicos entre os solos estudados. A mineralogia da fra??o argila dos solos estudados ? constitu?da principalmente por caulinita, gibsita, anat?sio, goethita, ferridrita, hematita e maghemita e a mineralogia da fra??o areia ? composta principalmente por quartzo e ferridrita. No MTo foi detectado uma fra??o magn?tica com propor??o significativa de Fe2+, podendo estar relacionado com o material de origem e a fertilidade natural desse solo. Por meio das an?lises qu?mico-estruturais de microscopia eletr?nica de varredura e espectroscopia por dispers?o de energia de raios x (MEV e EDS), verificou-se maior teor de ?xido de ferro na fra??o areia do LVd2 e na separa??o magn?tica, o maior teor foi encontrado no LVd3. Os teores mais baixos de ?xidos de ferro foram encontrados no MTo, o que indica um menor intemperismo desse solo. Os Latossolos (mais intemperizados) apresentam baixa fertilidade natural, o Nitossolo apresenta m?dia fertilidade natural e o Chernossolo (menos intemperizado) elevada fertilidade natural. As an?lises de Correla??o de Pearson resultaram em alguns casos, em efeitos positivos sobre nutrientes, ou seja, quanto maiores os teores de Fe2O3 ou Fe, maiores foram as concentra??es de alguns macro e micronutrientes no solo. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Produ??o Vegetal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2014. / ABSTRACT Iron oxides , indicators of pedogenic factors, including the dominant lithology in source material, reveal diagnostic pedo-environmental characteristics, even as a basis for hierarchical clustering, and also, in many circumstances thereof, the agricultural potential of soils , particularly in tropical areas of the globe. Magnetic soils are those with high total content of iron oxides and high spontaneous magnetization. Products of weathering of basic rocks, magnetic soils have chemical and physical properties that allow its operation (or use) for both subsistence farming or for commercial purposes. In the Serra do Espinha?o - SdEM, and Upper Valley of Jequitinhonha ? AVJ, magnetic soils are originated from gabbros and green shales. The present study aimed to characterize morphologically, chemically, physically, mineralogically and chemical-structurally, seven magnetic soils as well as the AVJ and SdEM. The following soils were described, sampled and classified: Typic Haplustox ? LVd1 (Couto de Magalh?es de Minas), Rhodic Kandiustox ? NVdf (Planalto de Minas), Typic Haplustox ? LVd2 (Turmalina), Rhodic Haplustox ? LVdf (Pinheiro), Rhodic Haplustox ? LVd3 (Serra Azul de Minas), Rhodic Haplustox ? LVd4 (Pedro Lessa) and Typic Argiustoll - MTO (Carbonita/Estiva de Cima). Chemical analysis, granulometric analysis were performed through mineralogical analysis by diffratometry of x-ray, electronic scanning microscopy and spectroscopy of energy dispersive and M?ssbauer. It was determined the total content of oxides of Fe, Al, Ti, Mn and Si by means of sulfuric acid attack and calculated the molar ratios Ki and Kr .The results show striking differences between, chemical, morphological and physical and minerological attributes between studied soils. Positive correlations were found between the iron oxides and micronutrients. The the clay fraction mineralogy of soils consists mainly by kaolinite, gibbsite, anatase, goethite, ferrihydrite, hematite and maghemite and mineralogy of the sand fraction is composed mainly of quartz and ferrihydrite. In MTO, a magnetic fraction with a significant proportion of Fe 2+ was detected, which may be related with the source material and the natural fertility of the soil. Through chemical analysis, structural spectroscopy and scanning electron microscopy spectroscopy of energy dispersive of x-ray (SEM and EDS), a higher content of iron oxide was found in the sand fraction of the LVd2, and in the magnetic separation, the highest content was found in LVd3. The lower levels of iron oxides in MTO were found thus indicating that a minor weathering over the soil. The Oxisols (more weathered ones) have low natural fertility, .Nitosols presents average natural fetilidade, and Chernosol (less weathered ones), high natural fertility. The Pearson correlation analyses resulted, in some cases, into positive effects on nutrients, that is, the higher the content of Fe2O3 or Fe, higher concentrations of some macro and micronutrients in the soil were.