Effect of pastures on soil fertility in crop production systems under no-tillage after ten years

• Autor(a) principal: Santos, Henrique Pereira
• Data de Publicação: 2007
• Outros Autores: Fontaneli, Renato Serena, Spera, Silvio Tulio, Tomm, Gilberto Omar
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Pesquisa Agropecuária Gaúcha (Online)
• Texto Completo: http://revistapag.agricultura.rs.gov.br/ojs/index.php/revistapag/article/view/255
• topic: crop rotation, ley farming, annual pasture, perennial pasture.; rotação de culturas, integração lavoura-pecuária, pastagem anual, pastagem perene.

The objective of this study was to assess the soil fertility on a typical dystrophic Red Latosol (Typic Haplorthox) located in Passo Fundo, State of Rio Grande do Sul, Brazil, ten years after the introduction of mixed production systems, using production systems integrating grain production with pastures under no-tillage. Four production systems were evaluated: system I (wheat/soybean, white oat/soybean, and common vetch/corn); system II (wheat/soybean, white oat/soybean, and grazed black oat + grazed common vetch/corn); system III [perennial-cool season pastures (fescue + white clover + red clover + birdsfoot trefoil)]; system IV [perennial-warm season pastures (bahiagrass + black oat + rye grass + white clover + red clover + birdsfoot trefoil)]; and system V (alfalfa as hay crop), which was established in an adjacent area in 1994. The areas under systems III, IV, and V returned to system I after the summer of 1996. The systems I, II, III, IV e V increased the soil contents of organic matter, extractable P, and exchangeable K, mainly at 0-5 cm depth. The systems I, II, III, IV e V organic matter, exchangeable Al, extractable P, and exchangeable K levels decreased from the 0-5 cm layer to the 20-30 cm layer, while the opposite occurred with pH and exchangeable Ca and Mg contents.