Autores
V. T. Paulino; E. M. C. Teixeira; E. A. Schammass; M. A. C. Lucena; G. Gutmanis
Resumo
Integrated crop-livestock systems have attracted more interest in the last few years due to their capacity of improving stability and sustainability of agricultural systems when compared to more specialized production systems (Souza et al., 2008). The crop-livestock integration is an effective technique, but complex to maintain pasture productivity and its recovery, whose efficiency depends on soil physical management and its chemical fertility (Pariz et al., 2010). The inappropriate soil use and management invariably leads to compaction and loss of soil fertility that are characteristic of the pasture degradation process (Colet et al., 2009). The breakdown of the compacted layer can increase the forage yield and / or crops production in integrated crop-livestock system. Soil scarification promotes increases in soil macroporosity and total porosity, with a reduction in resistance to root penetration. Regarding the soil fertility, the corrective practices generally begins with the liming due to the high acidity of most brazilian soils, and low levels of Ca and Mg in the exchange complex and high Al saturation. In areas of crop-livestock systems liming corrects surface acidity potential. However, this practice can leave the subsoil with excess aluminum and lack of calcium, which inhibits root growth and affect the absorption of water and nutrients. The application of gypsum allows the improvement of the subsoil, reducing Al saturation and increasing levels of calcium and sulfur (Vitti et al., 2008). The aim of this study was to evaluate the effects of gypsum and lime application in an integrated crop-livestock system (ICL) with Brachiaria brizantha cv. Marandu and Piatã, B. ruziziensis and maize on yields of dry matter, crude protein and in vitro digestibility of these forages.
