Edge Influence Over Functional Tree Traits in an Atlantic Forest Remnant

Abstract

Habitat fragmentation is one of the leading causes of edge genesis and its effects. Functional tree traits such as wood density, height, and diameter are essential variables from which it is possible to infer several ecological processes. This study assessed the variability of the functional traits of trees over two habitats (edge and interior) of a forest remnant. The hypothesis tested were i) the functional traits would have lower values at the edges than the interior, and ii) environmental variables would influence such differences. This study was carried out in the largest Atlantic Forest remnant within Serra da Tiririca State Park, Brazil, by establishing ten plots (50 × 20 m) among different habitats. Within each plot, wood samples were taken from all trees with a diameter of = 10 cm. It was recorded the altitude, distance from the plots to the edge, and fire records as possible explanatory variables (environmental variables). Wood density was obtained using the immersion method. To verify differences in functional traits by habitat, the Wilcoxon test was applied. Additionally, the influence of explanatory variables on functional traits through generalized linear models was evaluated. One hundred eighty-five trees were recorded at the edges and 218 trees at the interior of the remnant. Wood density and tree height were significantly lower in the edges than in the interior. Furthermore, the best models indicated significant relationships between wood density and habitats, as well as diameter and distance to the edge. This study was effective in raising suitable variables to predict edge effects.

Forest Fragmentation in an Unregulated Protected Area on the Atlantic Coast of Brazil

“…According to Murcia (1995), Primak and Rodrigues (2001), Cunha et al (2021) and forest fragmentation encourages the abrupt contact of one ecosystem to the other, generating border effects. The border effect contributes to the interference in wind intensity, excessive sunlight, microclimate production, noise, and the entry of invaders that increase disturbances in the forest fragment (Volotão, 1998, Zuñe-da-Silva, 2022.…”

Impactos antrópicos na composição florística e funcional dos mecanismos de regeneração em um fragmento florestal urbano do Planalto Atlântico Paulista, Sudeste do Brasil1

“…Apesar das diferenças nos atributos da densidade da madeira e da massa das sementes estarem associadas às estratégias de regeneração das espécies arbóreas, a seleção de espécies de crescimento rápido nos mecanismos de regeneração demonstra que o processo de secundarização florestal encontra-se estabelecido no fragmento. Muitas espécies presentes nos mecanismos de regeneração estão adaptadas aos distúrbios locais, sendo árvores de menor porte, e seu recrutamento contínuo pode promover mudanças graduais na estrutura vertical do fragmento do GRU e ocasionar uma sucessão retrogressiva a estádios pioneiros, alterando sua composição florística e funcional (Tabarelli et al 2008, Dalling & Brown 2009, Santo-Silva et al 2013, Comita et al 2007, Zuñe-da-Silva et al 2022, Sfair et al 2016.…”