Desempenho agronômico da soja, fertilidade e dinâmica da matéria orgânica em solos sob aplicação de biochar no cerrado brasileiro

• Autor(a) principal: Lima, Larissa Borges de
• Data de Publicação: 2014
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• dARK ID: ark:/38995/0013000002whp
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tde/3024
• topic: carvão vegetal; produtividade; substâncias húmicas; charcoal; humic substances; productivity; AGRONOMIA::CIENCIA DO SOLO

The objective of this work was to verify the long-term effect of biochar application on soil chemical properties and the development and soybean yield and carbon pools in a Oxisol (Experiment I) and Haplic Plinthosol (Experiment II) in the cerrado biome. Both experiments were conducted under field conditions in Nova Xavantina-MT . Settled experiments in a randomized block design, consisting of the combination of levels of the fertilizer (NPK) and doses of biochar. For evaluation of soil fertility soil samples were collected at 0-20 cm and analyzed the following attributes: pH, Ca, Mg, H+Al, P, K, and organic matter (OM). Agronomic variables were: height and dry matter of V4 and R1 and productivity. For evaluations in carbon pools contents were determined and total organic carbon (TOC) and nitrogen (TN), the concentrations of C in fractions fulvic acids (FA) , humic acids (HA) and humin (HU) , and , humification index (HI) . In general , there was synergy between the effect of mineral fertilization and application of biochar on soil chemical over the four years after the application attributes. As the aromatic structures are oxidized biochar notes positive effect on the contents of OM. The productivity was significantly increased mainly due to the application of 16 Mg ha-1 of biochar on 1st 3rd and 4th year , with an equation with quadratic behavior . In the 7th and 8th grade direct effect of biochar was reduced with low variation of grain yield. An increase in TOC stocks and aromatic contents with increasing carbon biochar application, showing that Walkley-black method is not effective for the determination of TOC in soils under application of biochar. There was a reduction in C-AF and C-AH with the application of biochar , more evident effect in the presence of NPK . The C-HU increased significantly with increasing doses of biochar. High doses of biochar (>16 Mg ha-1) provide increased IH. In both experiments I and II, biochar contributes to increasing C more stable OM of soil fraction is humin , which is desirable from an environmental standpoint and fertility.