Tree-Fall Gaps Effects on Spider (Araneae) Assemblages in an Atlantic Forest Landscape in Northeastern Brazil

Abstract

The study investigates the effect of spatial and temporal tree-fall gaps structure on spiders' assemblage in an Atlantic forest fragmented area in Brazil. It was conducted in the Michelin Ecological Preserve-REM (Bahia), 190 ha forest remnant. Samples were collected on leaf-litter (50 × 50 cm) at five tree-fall gaps formations (<150 m 2), within five adjacent primary forest and five inner edge parcels. During 16 months (between May 2009 and October 2012), 480 m 2 leaf-litter samples were collected, from which spiders were extracted using mini-Winkler traps. The observed and estimated richness of spider's species was higher at the edge (p < 0.01). The habitat structures differ significantly among the three habitat types (MRPP, p < 0.01) and also during the tree-fall gaps aging gradient (MRBP, p < 0.01). There were significant differences on spiders' species composition, comparing the three habitats (MRPP, p < 0.05). The composition of spider's species changed as tree-fall gaps aged (MRBP, p < 0.05). We argue that the tree-fall gaps play, on a local scale, an important role in acting on the time-space distribution dynamics of spider's species assemblages, although the time effect should still be evaluated.

Are Leaf-Litter Ants (Formicidae) Distributed Differentiated between Inner Zones of Natural Treefall Gaps?

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Comparisons of the composition of spider assemblages in three vegetation habitats in Bogor, West Java, Indonesia

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Soil Macrofauna Abundance and Diversity Under Trees Woodlots in Eastern Democratic Republic of Congo

“…In addition, high herbaceous vegetation coverage together with fallen trunks constitute a suitable booster and support for fixing the spiders' webs. Consequently, based on the distinctiveness of microhabitats and microclimate created by the amount of light perceived, forests and non-forests systems are differently constituted in terms of Araneae abundance (Peres et al, 2014).…”