Effects of invasion by Tradescantia zebrina Heynh. on tree species regeneration in a secondary Atlantic Forest fragment, in Londrina (PR).
Currently considered as one of the major causes of the loss of biodiversity on the planet, invasive alien species cause serious problems to natural ecosystems, leading many native species to become locally extinct. Surprisingly, invasions can come from ordinary sources, such as home gardens. This study aimed to verify the invasive impact of Tradescantia zebrina Heynh., a exotic ornamental herb, on tree regeneration of a secondary Atlantic Forest fragment where the understory is partly dominated by T. zebrina. To test the hypothesis that T. zebrina is limiting the recruitment of native tree species, plots were placed in non-invaded and invaded sites. All tree seedlings between 10 cm and 1 m tall were recorded, and the composition and structure of regeneration were compared between treatments. Tradescantia zebrina proved to be a strong competitor because it influenced abundance and species richness. Although there are reports in the literature of using non-selective herbicides, it is urgent to carry out further studies on how to control T. zebrina with the goal of restoring native vegetation.