J Plant Ecol ›› 2019, Vol. 12 ›› Issue (4): 713-721 .DOI: 10.1093/jpe/rtz009

• Research Articles • Previous Articles     Next Articles

Fraying around the edges: negative effects of the invasive Tradescantia zebrina Hort. ex Bosse (Commelinaceae) on tree regeneration in the Atlantic Forest under different competitive and environmental conditions

Wagner A. Chiba de Castro1,*, Rafael O. Xavier2, Federico H. L. Garrido1, Jair H. C. Romero3, Cleto K. Peres1 and Ruberval C. da Luz1   

  1. 1 Instituto Latino-Americano de Ciências da Vida e da Natureza, Universidade Federal da Integração Latino-Americana (UNILA), Foz do Iguaçu, PR, 85867-970, Brazil
    2 Departmento de Ecologia, Universidade de São Paulo, São Paulo, SP, 05508-090, Brazil
    3 Departamento de Hidrobiologia, Universidade Federal de São Carlos, São Carlos, SP, 13565-905, Brazil
    *Correspondence address. Instituto Latino-Americano de Ciências da Vida e da Natureza, Universidade Federal da Integração Latino-Americana (UNILA), Foz do Iguaçu, PR, 85867-970, Brazil. Tel: +55 45 999151360; E-mail: wagner.castro@unila.edu.br
  • Received:2018-07-26 Revised:2019-01-29 Accepted:2019-02-12 Online:2019-02-13 Published:2019-08-01

Abstract:

Aims

Invasive plants modify the structure and functioning of natural environments and threat native plant communities. Invasive species are often favored by human interference such as the creation of artificial forest edges. Field removal experiments may clarify if invasive plants are detrimental to native plant regeneration and how this is related to other local factors. We assessed the joint effect of environment and competition with the invasive Tradescantia zebrina on tree species recruitment in an Atlantic Forest fragment.

Methods

We carried out the experimental study in the Igua?u National Park, located in southern Brazil, using 30 plots distributed across five invaded sites during 6 months. We counted T. zebrina leaves and recorded the abundance and height of tree recruits over time under contrasting environmental (forest edge vs. forest interior) and removal (all aboveground biomass, only T. zebrina removal, and control) treatments. We analyzed the effects of environment and removal treatment using generalized linear mixed models.

Important Findings

The invasive species performed better at the forest edge than in the interior. The higher competitive pressure of T. zebrina led to higher mortality and lower height of tree recruits. Invader removal favored tree recruitment, especially in the forest interior. Our study shows that T. zebrina hampers woody species regeneration in tropical Atlantic Forests, especially at the forest edge.

Key words: plant invasion, competition, forest edge, plant recruitment, Tradescantia zebrina, inch plant, removal treatment