Invasão biológica de Casuarina equisetifolia na Restinga da Massambaba: Estrutura, Riqueza e Regeneração

• Autor(a) principal: Fontes, Alessandro Henrique Nunes Branth
• Data de Publicação: 2013
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UERJ
• Texto Completo: http://www.bdtd.uerj.br/handle/1/7945
• topic: Degraded área; Invasive species; Exotic species; Management; Restinga; Area degradada; Espécie invasora; Espécie exótica; Manejo; Restinga; Angiosperma - Arraial do Cabo (RJ); Bioinvasão; CNPQ::CIENCIAS BIOLOGICAS::ECOLOGIA::ECOLOGIA DE ECOSSISTEMAS

Biological invasion is seen as the process of introduction and adaptation of species that are not part of a particular ecosystem and is considered the second greatest cause of biodiversity loss. Casuarina equisetifolia is an angiosperm well adapted to environments with high salinity levels and low water content representing a major threat to biodiversity loss in coastal environments cause it rapidly colonize degraded areas in these environments. This study aimed to assess the effects of the invasion of C. equisetifolia in species diversity and community structure in a fragment at the Restinga da Massambaba. Were allocated 46 plots of 10m x 10m in five different areas near to each other called: management, fire, intrusion, restinga and control. Through the Non Metric Multidimensional Scaling (NMDS) found that there is difference in floristic composition between invaded and non-invaded areas, but between areas invaded the composition is the same. Even the treatments being close to each other, ANOVA showed a significant difference in density of C. equisetifolia showing that external factors influence the structure of the population in these treatments. The herbaceous habit was prevalent in areas of differing invasion of the area where the shrubby habit control is the most significant. Zoochory was the dispersion syndrome predominant in all areas, except in the area of fire and invasion, where anemochory obtained the same number of species. The ANOVA indicated that the richness of the control area is much greater than the richness in the areas of invasion. The invasion areas have a Shannon index ranging from 0.23 to 1.4, while the control region has an index of 2.49, showing how C. equisetifolia lets the flora homogeneous, enabling a few species able to colonize these environments as Pilosocereus arrabidae, Schinus terebinthifolius and Varronia curassavica. Linear regression indicated that the richness decreases with increasing density C. equisetifolia.