Integração lavoura pecuária: efeitos no solo, na forragem, modelagem e simulação econômica

• Ano de defesa: 2010
• Autor(a) principal: MUNIZ, Luciano Cavalcante
• Orientador(a): FRANCA, Aldi Fernandes de Souza
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Goiás
• Programa de Pós-Graduação: Doutorado em Ciência Animal
• Departamento: Ciências Agrárias
• País: BR
• Palavras-chave em Português: fertilidade do solo; biologia do solo; idade da pastagem; estoque de carbono no solo; modelagem de sistema de produção; 1. Fertilidade do solo 2. Biologia do solo 3. Idade da pastagem 4. Estoque de carbono no solo 5. Sistema de produção - modelagem
• Palavras-chave em Inglês: soil fertility; soil biology; pasture age; carbon stock on soil; production system modeling
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::ZOOTECNIA::PRODUCAO ANIMAL
• Link de acesso: http://repositorio.bc.ufg.br/tede/handle/tde/1089

When approaching the crop-livestock integration (CLI) theme, the present thesis had as one of its main objectives to evaluate the alterations in the soil-plantanimal- environment components exercised by the crop and pasture rotation dynamics in crop and livestock integration system. Two adjacent areas, one representing the natural environment (original cerrado vegetation) and other the degraded pastures served as reference ( control ) to the inferences performed. The experiment was performed at a 92 ha area, divided into six paddocks of approximately 15 ha, where the annual crops and pastures rotation was made. The soil samplings were collected at the 0-10, 10-20, 20-30, 30-40 and 40-50 cm layers. There was an increase in the carbon contents of the microbial biomass, in the microbial quotient and in the organic matter on the soil and reduction in the metabolic quotient at the pastures chronological sequence environments, at the crop-livestock integration system, in comparison with the degraded pasture. The different pastures stages within the crop-livestock integration system stocked the average of 17,67 Mg ha-1 carbon more than the degraded pasture up to a 50 cm depth. The Cerrado contained the most carbon stock and the degraded pasture the least among all the environments studied. There was a significant decrease in the phosphor and potassium contents in relation to the pasture age increase and an increase in the calcium and magnesium contents. Micronutrients contents among the treatments evaluated presented values above the demand for capim- Marandu. The capim-Marandu samplings were performed in five different seasons of the year (winter, beginning and end of spring, summer and autumn). Quantitative and qualitative alterations at the forage were observed during the experimental period. Changes on the structural components green leaf, green stem and dead material, as well as on DM (Dry Matter), GP (Gross Protein), TDN (Total Digestive Nutrients) and FND (Fiber in Neutral Detergent) contents, among others, characterized the forage on the different periods. The qualitative variations among the forages are of high magnitude, being outlined the significant drop on GP (Gross Protein) and TDN (Total Digestive Nutrients) contents according to the pasture maturity development. All pastures chronological sequence treatments, after 2,5 years of crop, resulted in favorable evaluations, having P1 treatment as the best investment option with NPV (Net Present Value) equals to R$144,34 followed by P2 treatment with R$112,61 and P3 with R$58,54, indicating to be a favorable Project. There is indication on the present work that the biggest loss in relation to the obtained economic advantages happens already from the second year after the pastures establishment. Such results may constitute important implications at CLI systems planning. Carbon bonus at pasture based animal production system may be a financial incentive for the producer to join the pastures rotation with annual crops. Nevertheless it is necessary that studies are performed to quantify emissions of gases responsible for greenhouse in order to verify whether the result represents a bonus or an environmental onus to the producer.