Invasion impact by Pteridium arachnoideum (Kaulf.) Maxon (Dennstaedtiaceae) on a neotropical savanna

Abstract

Whether management intervention is required to control biological invasions depends primarily on demonstrating species losses resulting from such invasions. Brackens of the Pteridium genus are currently regarded as a problem species that act as important ecological filters in the assembly of invaded communities. We investigated the effects of Pteridium arachnoideum invasion on the diversity, structure, floristic composition, and functional traits of cerradão in Assis, São Paulo, Brazil. We compared an invaded site with an adjacent non-invaded site. Bracken constrained the establishment of tree species, resulting in a community structure remarkably distinct from the non-invaded area. The density and basal area of the arboreal community were higher in non-invaded areas, but large trees were more frequent in the invaded areas. However, bracken did not reduce tree species diversity. Both richness and diversity were higher in the invaded area, indicating that over time, tree species richness and diversity naturally recovered, albeit slowly, in the invaded area. Therefore, one cannot attribute the loss of richness in the Cerrado vegetation to bracken invasion. Hence, we argue that, in this system, eradication of this invasive species is not likely to be cost effective, and thus, it should be a low management priority.

Restoration Strategies in an Area Invaded by Pteridium aquilinum (L.) Kuhn

“…A similar result was observed by Cervasio et al (2009), who tested methods of bracken control in Italy, verifying the efficiency of harrowing since the number of individuals was reduced and the natural regeneration of native species induced. Pteridium aquilinum is a rhizomatous plant (Guerin & Durigan, 2015). In general, the rhizomes and their rhizophores are deeply buried, allowing the bracken to withstand environment adversities, acting as a storage organ, besides having expansion properties, facilitating the colonization and fixation of the plant in the environment (Atkinson, 1989).…”

Fire has short-term negative effects on a super-dominant native fern, Pteridium arachnoideum (Dennstaedtiaceae), in a Brazilian savanna

“…Thus, considering that P. arachnoideum has been shown to dominate other Neotropical savannas after repeated fires (Alonso-Amelot & Rodulfo-Baechler, 1996) and that a previous study showed decreasing impacts of P. arachnoideum in Cerrado sites in the absence of large disturbances (Guerin & Durigan, 2015), it is possible that a fire feedback loop also will be observed in the Cerrado. Such feedback would depend on whether P. arachnoideum recovers rapidly after fire events.…”

<b>Ferns influence on the woody species seedling bank in semi-deciduous forest, Southern Brazil

“…Several studies on the impact of ferns on plant communities have been carried out in the world (George & Bazzaz, 1999;Walker et al, 2010;Gallegos et al, 2015), but almost nothing was published about this subject in Brazil (Silva & Silva Matos, 2006;Silva Matos & Belinato, 2010;Guerin & Durigan, 2015), specially in seasonal semideciduous forest (SSF). Knowledge about the influence of herbaceous stratum on tree regeneration is essential for conservation and reforestation programmes of these forests.…”