Data Set Owner(s): Dr. Alan N. Costa Universidade Federal de Uberlndia Instituto de Biologia Rua Joo Naves de vila, 2121 - Campus Umuarama Uberlndia, MG 38400-902 Brazil E-Mail: alan_nilo@yahoo.com Webpage: http://lattes.cnpq.br/8925220882354299 Key words: Atta laeivigata Attini Formicidae Seedling Herbivory Gradient ecosystem engineer Cerrado Brazil soil fertility canopy cover tropical savanna Geographic Coverage: Estao Ecolgica do Panga / Panga Ecological Station Uberlandia, Minas Gerais, Brazil Coordinates: West: 482344, South: 191045 Temporal Coverage: Begin: 2010-01-01 End: 2011-12-30 Project Info: Title: Do an ecosystem engineer and environmental gradient act independently or in concert to shape juvenile plant communities? Tests with the leaf-cutter ant Atta laevigata in a Neotropical savanna Funding: Alan N Costa was supported by a doctoral fellowship from Brazils Agency for the Support and Evaluation of Graduate Education (CAPES). EMB was supported by a CAPES Special Visiting Researcher Fellowship (Grant AUXPE-PVE-0205/2013). File: EnvData_ActiveNests.csv Description: Environmental data collected in plots at different distances from Atta laevigata nests at the Estao Ecolgica do Panga (Uberlandia, Minas Gerais, Brazil). Methods: A complete description of the methods is given in Costa et al. (2018) PeerJ. Briefly, litter biomass was measured by collecting all litter from a randomly selected half of each plot once during the 2010-2011 rainy season, drying it at 50 C for 72 h, and weighing it with a microbalance. To estimate above-ground grass biomass we dried and weighed all grasses from a randomly selected half of each plot. Canopy cover above each plot was estimated using photos analyzed with Adobe Photoshop (Adobe Systems Inc., San Jose, California, USA). In our analyses we used the average canopy cover in two photos taken during the same rainy season. Photos were taken with a Nikon Coolpix 950 from a height of 50 cm in either the early morning (6h) or early evening (18h). We estimated surface soil moisture content in plots at the end of the 2011 dry season by collecting a sample of the top 20 cm of soil from two points separated by 100 cm. These samples were bulked, weighed, dried at 50 C for 96h, then weighed again to estimate percent moisture content. As a proxy for soil compaction we used soil penetrability, which we measured at the end of the 2010-2011 rainy season by dropping a 1 m long x 5 mm diameter iron rod vertically from a height of 50 cm at three haphazardly selected points in each plot, measuring the depth to which the rod penetrated the soil at each point, and recording the average of these values. During the 2011 rainy season we selected N = 5 nests in Cerrado ralo and N=5 nests in Cerrado denso nests for analyses of soil chemistry. For each nest we collected soils in the plots on nest mounds and the plots 10m from nests. We collected 5 soil samples of ~100 g samples each from each plot: one from the plot center and one from each corner. The 5 samples from each plot were bulked into a single sample and taken to the Soils Analysis Lab of the Federal University of Uberlndia (UFU), where pH, P, K+, Ca2+, Mg2+, Al3+, and total organic matter were measured using standard protocols (EMBRAPA. 1997. Manual de mtodos de anlise de solo, 2a edio. Rio de Janeiro, Brazil: Produo de Informao-EMBRAPA). Column Headings: 1) Habitat: The habitat in which nests Atta laevigata nests were located. Codes: CD=Cerrado denso, CR=Cerrado ralo 2) Nest: the unique identification number assigned to each nest 3) plot.id: the unique identification number assigned to each plot surveyed 4) location: the location of the plot relative to the ant nest. Codes: Nest = center of the nest mound, Adjacent = edge of the nest mound, Far = 10 m from the edge of the nest mound 5) perc.cover: the percent canopy cover over a plot 6) litter.bmass: the mass of litter biomass in grams collected in a randomly selected half of the plot 7) soil.pen: the distance in cm to which a --- penetrated into the soil . 8) grass.bmass: the amount of grass biomass in grams collected in a randomly selected half of the plot 9) ph: the pH of soil the soil sampled in a plot 10) K: the K+ of of soil the soil sampled in a plot (cmolc/kg) 11) Ca: the Ca2+ of soil the soil sampled in a plot (cmolc/kg) 12) Mg: the Mg2+ of soil the soil sampled in a plot (cmolc/kg) 13) Al: the Al3+ of soil the soil sampled in a plot (g/Kg) 14) org.mat: the amount of organic matter in soil sampled in a plot (g/Kg) 15) soil.moisture.surface: the percent soil moisture content of soil sampled in the plot. 16) nest.area: the area of the Atta laevigata nest mound in square meters, estimated using the formula of an ellipse.