Adubação nitrogenada e locais de amostragens do Capim-Marandu em sistema silvipastoril

• Ano de defesa: 2011
• Autor(a) principal: Fernandes, Cellyneude de Souza
• Orientador(a): Garcia, Rasmo
• Banca de defesa: Fonseca, Dilermando Miranda da , Ribeiro, Karina Guimarães , Queiroz, Domingos Sávio
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Doutorado em Zootecnia
• Departamento: Genética e Melhoramento de Animais Domésticos; Nutrição e Alimentação Animal; Pastagens e Forragicul
• País: BR
• Palavras-chave em Português: Ureia; Radiação, Digestibilidade
• Palavras-chave em Inglês: Urea; Radiation; Digestibility
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::ZOOTECNIA::PASTAGEM E FORRAGICULTURA
• Link de acesso: http://locus.ufv.br/handle/123456789/1836

The experiment was conducted to evaluate the effect of nitrogen fertilizer management (dose and sources of N) and sampling position of Brachiaria brizantha Marandu in the understory in silvopastoral system on productivity, leaf/stem ratio, height, chemical composition, foliar nitrogen in the forage and variables of soil organic matter (SOM). A scheme of subdivided plot was adopted in space, in a randomized block designed with six replications to study the variables related to the plant Brachiaria. The main plot was the management of nitrogen fertilization (dose and source of nitrogen) and subplots positions of samples in the understory of the silvopastoral system (North, Central and South according to the planting of eucalyptus). The design for the study of soil variables was a randomized block with six replications and treatments of nitrogen fertilizer management: 50 and 100 kg ha-1 N in the form of urea, 50 and 100 kg N ha-1 in the form of ammonium sulfate and treatment control without nitrogen fertilization. The evaluated variables related to plant were: dry matter production (DMP), daily accumulation rate of dry matter (DARDM), blade/stem ratio (B / S), sward height (SH), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) and foliar nitrogen (FN). Considering the data of the first collection there was no significant interaction between factors management of nitrogen fertilization and sampling position on variables DMP, DARDM, B / S, SH, CP, NDF, ADF and FN. There was a significant effect of manure management nitrogen on DMP, DARDM, B / S, SH and NDF, and significant effect of sampling position on DMP, DARDM, B / S, SH, NDF and ADF. Considering the data from the second collection no significant interaction between factors management of nitrogen fertilization and sampling position on variables DMP, DARDM, SH , CP, NDF, ADF and FN, there was a significant effect of nitrogen management on SH, CP, NDF, ADF and FN, and there was a significant effect of sampling position on DMP, DARDM and SH. The dynamics of SOM was studied by analysis of the following variables: total organic carbon (TOC), total nitrogen (TN), carbon/nitrogen ratio (C / N), microbial biomass carbon (MBC) and microbial biomass nitrogen (MBN). For these variables there was no significant affect from the management of nitrogen fertilization. The general average values of TOC, TN, MBC and MBN were respectively 2.05, 0.16, 5.32 and 1224 kg dag-1, and 13.34 kg dag-1 of C / N ratio. In silvopastoral system consisting by the association Brachiaria brizantha Marandu and eucalyptus in period of months of the year without limitation of temperature and humidity to the nitrogen fertilization increase the values of productive variables of the pasture (DMP, DARDM and SH), only change the NDF as to the variables of chemical composition of the pasture, not altering the dynamics of SOM and being recommended to use the highest N rate (100 kg N ha-1), and sampling position in the understory affects the productive of the pasture and the components of cell wall.