ABOVEGROUND AND TOTAL ROOT BIOMASS COMPONENTS OF Brachiaria PASTURES IN DIFFERENT AGES AFTER RENOVATION AS A PRODUCTION INDICATOR UNDER SAVANNA VEGETATION

This study aimed to evaluate the production components of aboveground and total root stock biomass of Brachiaria pastures of different ages after renovation. Three B.brizantha pastures, with one, seven, and nine years after renovation through the Barreirão system, and one B. decumbens pasture twenty...

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Detalhes bibliográficos
Autores: Santos, Renato Sérgio , Mota dos, Oliveira, Itamar Pereira de, Morais, Rafael Fiusa de, Urquiaga, Segundo Caballero, Boddey, Robert Michel, Alves, Bruno José Rodrigues
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2007
País:Brasil
Recursos:Universidade Federal de Goiás (UFG)
Repositorio:Pesquisa Agropecuária Tropical (Online)
Idioma:portugués
OAI Identifier:oai:ojs.revistas.ufg.br:article/1837
Acesso em linha:https://revistas.ufg.br/pat/article/view/1837
Access Level:acceso abierto
Palavra-chave:Brachiaria
pastures
roots
litter
Braquiária
pastagem
raízes
liteira
Descrição
Resumo:This study aimed to evaluate the production components of aboveground and total root stock biomass of Brachiaria pastures of different ages after renovation. Three B.brizantha pastures, with one, seven, and nine years after renovation through the Barreirão system, and one B. decumbens pasture twenty years after traditional renovation were evaluated. The areas were located at Goiânia, Brazil (16º35'12";S, 49º21'14";W, 730 m). The one year after renovation pasture showed the highest productivity, 197% higher than the twenty year after renovation pasture. With increasing pasture renovation age, there was a production and regrowth rate decrease due to the degradation process. This aspect may be observed in the root system development, since the total root productivity to 100 cm depth was reduced as pasture age increased, with 9.14 Mg ha-1, 4.87 Mg ha-1, and 2.90 Mg ha-1 for pastures of seven, nine, and twenty years after renovation, respectively. The one year pasture did not show appreciable root contribution. The Brachiaria regrowth pasture was found to be dependent on system N availability; hence, the litter production showed to be a good pasture degradation indicator. The N stocks down to 100 cm depth were of 7.54 Mg ha-1, 8.70 Mg ha-1, and 9.47 Mg ha-1, in the pastures with one, seven, and twenty years, respectively. These values were much lower than those in the nine year after renovation pasture (14.2 Mg ha-1). KEY-WORDS: Brachiaria; pastures; roots; litter.