Forest degradation by grazing: a case study in the northern Colombian amazon

It is known that the expansion of the agricultural frontier and the expansion of the grazing frontier have caused deforestation and fragmentation of the Amazonian forests. However, it has not been determined whether cattle grazing degrades forests. Therefore, we established edge-to-interior transects in three contrasting environments of tropical rainforests of the northern Colombian Amazon, corresponding to: forested areas with cattle pressure (grazing), forests adjacent to unused pasture cover, and forests adjacent to rubber plantations. In each transect, variations in the attributes of composition, structure and diversity of natural regeneration were analyzed. It was found that ungrazed forests have greater diversity in the natural regeneration and presence of transcendental species in the successional dynamics. In comparison to the grazed forests, in which specific patterns of disturbed environments were observed, such as the presence of generalist species, heliophytes, herbaceous habits and rapid colonization that can hinder the recruitment of forest species. In forests adjacent to rubber plantations, a greater diversity of forest species of heliophyte and sciophyte guilds was recorded. This characterization provides a better understanding of the interaction of livestock activity with resources such as biodiversity, showing the need to direct livestock management to practices that limit grazing in forested areas so as not to drastically affect their ecological dynamics.