Qualidade do solo em área de Mimosa artemisiana Heringer & Paula, Acacia mangium Wild, Eucalyptus grandis x Eucalyptus urophylla, floresta secundária e pastagem, em Além Paraíba, MG

Abstract

This study was conducted at Fazenda Cachoeirão (Cachoeirao Farm) in Além Paraíba, Minas Gerais, between April 2008 to June 2009. The topography of the region is rugged with strong, undulated and mountainous relief. The aim of this study was to evaluate the quality of the soil under forest stands compared to pasture and secondary forest. Soil assessments were made in depths of 0 - 5 cm and 5 - 10 cm. Also an analysis was performed regarding the fertility and organic carbon content (Corg) of the soil, in addition to physical analysis: bulk density (BD), particle density (Dp), total porosity (VTP%) and aggregate stability analysis. For BD the layer of 10 - 20 cm was also evaluated. The depth of 0 - 5 cm showed the best differentiation among the areas with respect to aggregate stability. There was no significant difference in the other variables. We also analyzed the litter produced by these different types of vegetation, with exception of the pasture. Carried out to quantify the litter layer on the soil, its rate of decomposition, nutrient content and quantity of nutrients in the litter layer. The sampling of accumulated litter was taken in June 2008 and June 2009. It was found that the litter of eucalyptus and acacia is the one that promotes the best soil cover. Another study was related to the composition of soil fauna in these areas. For the collection of organisms, we used pitfall traps (pitfalls). The samples were taken in the dry and rainy seasons. It was determined the activity of the fauna, total and average wealth index, Shannon diversity index, Pielou index, relative composition of functional groups and index V. In general, the secondary forest had higher abundance of soil fauna.