Caracterização física, química, mineralógica e micromorfológica dos solos da serra Sul, Floresta Nacional de Carajás, Pará

• Ano de defesa: 2009
• Autor(a) principal: Ribeiro, Acauã Santos de Saboya
• Orientador(a): Schaefer, Carlos Ernesto Gonçalves Reynaud
• Banca de defesa: Simas, Felipe Nogueira Bello , Ferreira Júnior, Walnir Gomes
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Mestrado em Solos e Nutrição de Plantas
• Departamento: Fertilidade do solo e nutrição de plantas; Gênese, Morfologia e Classificação, Mineralogia, Química,
• País: BR
• Palavras-chave em Português: Pedogênese; Amazônia; Geoambientes; Relação solo-vegetação
• Palavras-chave em Inglês: Pedogenesis; Amazônia; Geoenvironmental; Soil-vegetation
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::CIENCIA DO SOLO
• Link de acesso: http://locus.ufv.br/handle/123456789/5466

The Serra Sul, located in the southeastern portion of the Pará State, is the largest plateau in Serra dos Carajás, comprising highly preserved ecosystems developed on ferruginous rocks. Despite the great geological and economic importance of this region, which is the largest deposit of iron ore in the world, there are very few pedological studies. The objective of the present work was to study the soils of the main geoenvironments of Serra Sul, in terms of their morphological, physical chemical, mineralogical and micromorphological characteristics, seeking to understand the main factors and processes in this singular landscape. Thirtheen soil profiles were described and analyzed. Plintossolos Pétricos, with continuous (lithoplintic) or fragmented (concretionary) horizon, is the main soil type. There is a clear influence of soils on the distribution of the different phyto-physiognomies. Latossolos Vermelhos occur on forested slopes while Organossolos Háplicos occurs on flat, poorly drained grasslands. In general soils are acid, dystric, with very low P avilability and high Al3+. Soils located close to caves, poorly frained areas and termite mounds have high levels of available P, evidencing the effect of the fauna on soil nutrient status. The high levels of total organic carbon (TOC) in all soils indicate conditions which favor the incorporation and conservation of vegetal residues as soil organic matter. Soils have high levels of iron oxide obtained by both sulphuic attack and DCB extractions and present very strong red color. Expressive amounts of maghemita occur and, together with hematite and goethite, comprise the mineralogy of the clay fraction. Microanalysis illustrate the high Fe2O3 levels (> 80%) and very low SiO2 and macronutrient levels, which is attributed to the chemical composition of the parent material (jaspelite), which is rich in iron oxide and poor in nutrientbearing primary minerals. The results indicate that the iron-rich parent material and the pedoclimate are the main factors determining the characteristics of the sudied soils.