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Grasslands in southern Brazil have inherent characteristics favorable to forage production for domestic herbivores, which can be impaired or enhanced by management. The aim of this study was to evaluate the influence of management on plant characteristics, comparing commonly used techniques. The experimental design was bifactorial, the first factor consisting of four managements: burning, oversowing with annual winter forages, mowing and absence of interference, and the second factor was the time elapsed between management and evaluation. The experiment was conducted under field conditions, in a complete randomized block design with four replications. The LAI (leaf area index), dry mass production and crude protein content of the pasture were evaluated. Pasture management with oversowing showed higher LAI growth rate, as well as higher pasture dry mass production than the other treatments. There was no effect of the different managements on the crude protein content of the pasture, but of the time, with the highest value on the 53rd day. The results suggest that the adoption of management with oversowing of annual winter forages should be emphasized for the productive improvement of native grasslands in southern Brazil. [ABSTRACT FROM AUTHOR]

The southern region of the state of Minas Gerais, Brazil, is highly characterized by livestock breeding which, due to inadequate managements, has produced erosion issues frequently related to soil aggregation. Microorganisms are highly sensitive to soil managements and have a role in their aggregation. Current analysis studies the impact of the succession process in different pasturelands on microorganisms and its processes especially in aggregates with different class sizes which are important microbes that may be subject to interferences. Four pasture areas were selected from the sub-basin of the river José Pereira, Itajubá MG, Brazil, at different stages of secondary succession, in dystrophic red argosol: A1 - area at the first stage of succession and partially exposed soil; A2 - area in mid-succession stage and partially exposed soil; A3 - area without any succession, with totally covered soil; A4 - area with the highest succession stage, with great diversity of tree and shrub species and totally covered soil. Soil samples from areas under analysis were separated into three classes of aggregates with 0.5; 2.0 and 4.0 mm, prior to the determination of biochemical (microbial activity and biomass, metabolic quotient - qCO2) and microbiological (length of extra-radicular mycelium, density of bacteria, actinobacteria and total fungi) attributes. Pastures at different succession stages impacted differently soil microorganisms and processes. For most microbiological indexes, there was no effect or influence of aggregate size. Area with the most advanced secondary succession stage (A4) provided more activity, biomass and extraradicular mycelium when compared to the other areas. [ABSTRACT FROM AUTHOR]