Ciclagem de nutrientes em ecossistemas de pastagens tropicais

Abstract

The degradation of Brazilian pastures has been an increasing problem, especially in agricultural frontier regions, where the management practices adopted are inadequate, causing an imbalance in this ecosystem. Management practices that favor nutrient cycling appear in this scenario as an alternative for the recovery of degraded pastures. In the case of pastures, the largest reservoirs of nitrogen (N) and carbon (C) are the atmosphere, soil, plant species and grazing animals, being that the dynamics of these nutrients is controlled by biotic and abiotic factors. The litter and the animal excreta represent the main routes of return of the nutrients to the ecosystem through the decomposition by microorganisms. The use of legume species intercropped with pasture is a good strategy to increase soil nitrogen content, minimizing costs with nitrogen fertilization, in addition to improving the quality of the litter.