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BARRIERS TO ESTABLISHMENT OF NATURAL REGENERATION IN ABANDONED PASTURES

ABSTRACT

The pressure on rainforests due to fragmentation of natural landscapes has caused changes in the substitution pattern of the species present in the plant community. In the case of abandoned pastures, there is an increased environmental vulnerability to colonization by invasive exotic grasses, which represent a barrier to the establishment of native plants, since the dispersion and seed germination until the later stages of their development. We proposed to discuss some of the processes of natural regeneration in pastures, addressing issues that hinder the recruitment of desirable woody species and, in this context, the exposure of some methodologies based on the concept of nucleation that can help this process. Through understanding of the mechanisms involved in the maintenance of plant communities, we observed that the seed germination and seedling recruitments are crucial steps in the process of vegetation restoration. Because only a narrow range of conditions is suitable (safe sites) for the recruitment, successful regeneration depends on the environment ability to provide an appropriate bed for germination (seedbed). The use of methodologies that aimed the natural regeneration, to be effective in pasture areas, should be technically well established and adequate to the local reality, because although they have promising initial results, may no longer be effective over time.

Keywords:
inhibitory grasses; nucleation; safe sites; seedbed

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