Drivers of community assembly in tropical forest restoration sites: role of local environment, landscape and space

This dataset is related to species and functional composition of dung beetles sampled in a chronosequence of 15 forest restoration areas located in the Atlantic Forest, Brazil. It is also possible to find information about local environmental conditions, landscape context and spatial patterns of these restoration areas. Dung beetles were sampled in 15 restoration areas of different ages (0 - 18 years), located within Veracel Celulose Company landholding, in the south of Bahia state, Brazil (16°06' - 16°23' S, 039°09' - 039°49' W). Between May 12^th and June 3^rd 2012 we selected 15 sites where the Veracel Celulose company was actively restoring previous pastureland to natural Atlantic Forest. The sampled restoration areas were distributed throughout the studied landscape, located at a minimum distance of 500 m and maximum distance of 75 km from each other. Dung beetle sampling was conducted using baited pitfall traps. Within each restoration site, we established a linear transect located 30-50 m from the edge, and placed a set of 3 pitfall traps at each of four sample points spaced 100 m apart along the transect, for a total of 12 traps per site. The three pitfall traps at each sample point were spaced 3 m apart and randomly assigned to receive a bait consisting of 25 g of either human feces, carrion (in this case bovine spleen), or rotten banana. Traps were left in the field for 48h and dung beetles were collected. All of them was identified to the genus level and, whenever possible, to species level. Dung beetles were also characterized according to their functional traits: size class, food relocation habit, diet and period of flight activity. Sampling sites were characterized using six environmental variables: canopy cover, understory cover, tree density, tree basal area, leaf litter depth, and soil percent sand. We measured canopy cover using hemispherical photographs with fisheye hemispherical lens. Photographs were analyzed using Gap Light Analyzer 2.0. To measure vertical understory cover, we took two photographs of the understory at each sample point using a black panel (1 × 1 m) arranged perpendicularly to the ground as a background. The camera was placed 1 m above the ground and pictures were taken vertically, aiming to the black panel. The photographs were analyzed with the software Sidelook 1.1, using the black pixels percentage of bichromatic pictures to calculate the vertical herbaceous vegetation density. We calculated tree density and basal area by recording the distance from the center of each sample point to the nearest four trees (circumference higher or equal to 10 cm at 1.3 m above soil) and measuring the DBH of those trees. Tree density was estimated as the average distance (cm) between the center of the sample points and trees. Finally, to estimate substrate heterogeneity across the 15 sites, we collected soil cores from 0-20 cm in depth, and estimated percent sand using granulometry analysis.We quantified key aspects of the landscape surrounding each of the 15 restored forest sites used to sample dung beetles. First, within a 1 km radius buffer surrounding each transect, we calculated the percentage of area that was natural forest (early, mid-stage and old-stage secondary forest and primary Atlantic forest fragments) and the percentage that was <i>Eucalyptus </i>spp. plantation. We next calculated a habitat patch proximity and availability index for each restoration site. This index was defined as: P = E (Dk/Ak) calculated based on the distance (D) from the edge of each of the 5 nearest fragments of preserved forest (k) and the area (A) of each fragment. Here we considered preserved forest as primary and old secondary forest. The habitat patch proximity and availability index is small when smaller fragments of preserved forest are distant from the restored area, and increases as fragments become larger and closer. The landscape metrics were quantified in Q-GIS using a digital map from a series of aerial photographs (1:100,000 scale) provided by Veracel Celulose SA.<br>