Navegando por Autor "Garcia, Fernando Henrique"

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    Impacto de diferentes doses de nitrogênio sobre a produção e composição bromatológica de capim Mombaça e atributos microbiológicos do solo
    (Universidade Estadual do Norte do Paraná, 2018-03-06) Garcia, Fernando Henrique; Porto, Petrônio Pinheiro; https://orcid.org/0000-0002-2999-7612; http://lattes.cnpq.br/1751366795715746; Porto, Petrônio Pinheiro; https://orcid.org/0000-0002-2999-7612; http://lattes.cnpq.br/1751366795715746; Matsumoto, Leopoldo Sussumu; https://orcid.org/0000-0001-5102-545X; http://lattes.cnpq.br/0857955043436449; Galbeiro, Sandra; https://orcid.org/0000-0003-0524-615X; http://lattes.cnpq.br/5040986607742686; Silva, Marcelo Alves da; http://lattes.cnpq.br/3283906522734749
    Nitrogen fertilization in pasture production can greatly boost yields, yet it may also cause undesirable environmental impacts. This study evaluated nitrogen fertilization using urea plus sulfur on the productivity and chemical composition of Mombaça grass, alongside effects on soil microbiological parameters. We assessed dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), ash, and the microbiological indicators microbial biomass carbon (MBC), metabolic quotient (qCO₂), and microbial quotient (qMic), in a Rhodic Eutrudox in the Northern region of Paraná. Twenty plots, each 4.0 × 4.0 m, were established with 1.0 m spacing between plots. The experiment used a randomized complete block design with four replicates; treatments comprised five nitrogen rates (0, 100, 200, 300, and 400 kg ha⁻¹ N) combined with 100 g sulfur per kg N, applied in split applications from September 2016 to March 2017 following each harvest. Dry matter yield increased from 6.92 to 20.07 t DM ha⁻¹ at 0 and 400 kg ha⁻¹ N, respectively, although agronomic efficiency per kg applied N declined. Forage chemical composition showed DM and ash contents decreasing from 33.13 to 26.27% and from 14.46 to 12.56%, respectively, across the same range, whereas CP content rose from 6.69 to 9.61%. Values of MBC, qMic, and qCO₂ were clearly affected by increasing N application rates: MBC and qMic decreased, while metabolic quotient (qCO₂) rose significantly. It is concluded that higher nitrogen rates improved Mombaça grass yield and nutritive value, but adversely altered the soil microbial community, indicating greater metabolic stress.