Atributos físicos e fracionamento granulométrico da matéria orgânica do solo em sistema de integração lavoura-pecuária

Abstract

The maintenance of productive agricultural systems is a great challenge for humanity. In that context, the soil and water preservation earns a special highlight, because it represents an important resource in agriculture production. The crop-livestock integration represents an interesting alternative soil management especially in regions with difficulties in maintaining cover crops in no-tillage system. The objective of this research was to evaluate soil physical and chemical attributes, assuming that the livestock-crop integration, when well managed, improves soil quality and provides greater stability in the system. The experimental design was completely randomized, with five repetitions. The treatments consisted of a 6 x 4 factorial, being 6 systems of crop rotation (S1, S2, S3, S4, S5 and forest) and 4 depths (0-5, 5-10, 10-15 and 15-20 cm). Livestock-crop integration was established in the area in 2003. The livestock-crop integration system changes soil physical attributes, and the effects of different systems are mainly expressed in the superficial layer of soil. The chosen management, that considers livestock-crop integration, with the descript rotations, allows us to keep soil carbon levels equal to those found in the native forest environment. The accumulated soil carbon levels still prove that the chosen management adopted are as efficient as the reported environment (M), being an important indicator of sustainability of the system in relation to soil conservation.