Diagnose nutricional de eucalipto e impacto da disponibilidade de água e nutrientes nos estoques de carbono do povoamento

• Ano de defesa: 2012
• Autor(a) principal: Lourenço, Helton Maycon
• Orientador(a): Neves, Júlio César Lima
• Banca de defesa: Martins, Lafayete Gonçalves Campelo , Paiva, Haroldo Nogueira de
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Doutorado 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: Eucalipto; Nutrição; Diagnóstico; Minicepas; Carbono do solo; Isótopos
• Palavras-chave em Inglês: Eucalyptus; Nutrition; Diagnosis; ministumps; Carbon soil; Isotopes
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::CIENCIA DO SOLO
• Link de acesso: http://locus.ufv.br/handle/123456789/1634

Currently,in Brazil, planted forests with different species and hybrids of Eucalyptus occupy an area of 4.5 Mha approximate. Normally, these areas have low fertility and therefore require nutritional supplementation for high yields. In tropical environments, where the radiation is not limiting, to maintain satisfactory flow of water and nutrients are essential for forest sustainability. Once leaf analysis reflect these flows it is a powerful tool for a correct recommendation of forests nutritional supplementation. However, not always the interpretation of results of these analyzes is easy, with very frequently subject to diagnostics error. The use of methods based on balance and nutrient equilibration allows a better results interpretation. In this sense, the DRIS index and balanced Kenworthy index has been highlighted as monitoring tools of nutritional eucalyptus forest. The successful use of these tools is dependent primarily on obtaining reliable norm, which in turn are obtained from populations which better reflect the potential for growth of a particular forest site. Forests with no nutrient limitation tend to accumulate higher amounts of carbon in their biomass, even above or belowground. The belowground biomass, due to chemical characteristics and be in direct contact with the soil, is the primary source of carbon for stable fractions of soil organic matter. The objectives of this study were to obtain nutritional norms for eucalypt ministumps, grown on clonal minigarden phase in a nursery, and for young eucalyptus forests in the extreme south of Bahia, and check the effects of supplementation with water + nutrients on carbon stocks in soil and eucalypt forests. We conclude that: a) The DRIS norms and IBKW adjusted for eucalypt ministumps were sensitive to the season in the year; b) the use of specific norms, which take into account the season, led to better results than general norm; c) The use of diagnostic methodsto evaluate the eucalypt ministumps equilibration and balance of nutrient is also useful to indicate the need for possible adjustments in the nutrient solution; d) In young eucalyptus plantations using plots that present growth close to potential is more suitable for the composition of the reference population and as a result of nutritional norms; e) The diagnostic methods have unearthed a strong tendency by limiting Ca in young eucalypt forests; f) When there is supplemental water and nutrients carbon stocks in forest biomass may increase; g) There was no effect of the increased availability of water on forest productivity, however there is a higher biomass of fine roots and as a result of an increase in soil C stocks; h) An excessive application of nutrients can lead to reduction in the content of carbon in the soil.