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Nitrogen availability and N-cycling dynamics across ecosystems play a critical role in plant functioning and species distribution. Measurements of 15N natural abundance provides a way to assess ecosystem N dynamics, and the range of nitrogen stable isotope values (δ15N) for plants in an ecosystem can indicate divergent strategies for N uptake. We tested the hypotheses that the N-rich seasonally dry forest would have higher soil and leaf δ15N and a smaller range of leaf δ15N values compared to the N-poor cerradão (savanna woodland). We measured N concentration and δ15N in two soil depths and leaves of 27 woody species in cerradão and 26 in seasonally dry forest. As expected, total soil N concentration decreased while soil δ15N value increased with soil depth. Regardless of soil depth, seasonally dry forest soils had higher δ15N and total N concentration compared to cerradão soils. Foliar δ15N values varied from −6.4‰ to 5.9‰ in cerradão and from −2.3‰ to 8.4‰ in seasonally dry forest plants. Phylogenetically independent contrasts analysis and comparisons of δ15N mean values of the most abundant species and species co-occurring in both sites confirmed the hypothesis of higher δ15N for seasonally dry forest in comparison to cerradão. These results corroborate the expectation of higher soil and leaf δ15N values in sites with higher soil N availability. However, except for the most abundant species, no across-site leaf-soil (δ15N leaf -δ15N soil) differences (Δδ15N) were found suggesting that differences in leaf δ15N between cerradão and seasonally dry forest are driven by differences in soil δ15N. Variation of leaf δ15N was large in both sites and only slightly higher in cerradão, suggesting high diversity of N use strategies for both cerradão and seasonally dry forest communities. [ABSTRACT FROM AUTHOR]

Background: Soil animal communities include more than 40 higher-order taxa, representing over 23% of all described species. These animals have a wide range of feeding sources and contribute to several important soil functions and ecosystem services. Although many studies have assessed macroinvertebrate communities in Brazil, few of them have been published in journals and even fewer have made the data openly available for consultation and further use. As part of ongoing efforts to synthesise the global soil macrofauna communities and to increase the amount of openly-accessible data in GBIF and other repositories related to soil biodiversity, the present paper provides links to 29 soil macroinvertebrate datasets covering 42 soil fauna taxa, collected in various land-use systems in Brazil. A total of 83,085 georeferenced occurrences of these taxa are presented, based on quantitative estimates performed using a standardised sampling method commonly adopted worldwide to collect soil macrofauna populations, i.e. the TSBF (Tropical Soil Biology and Fertility Programme) protocol. This consists of digging soil monoliths of 25 x 25 cm area, with handsorting of the macroinvertebrates visible to the naked eye from the surface litter and from within the soil, typically in the upper 0-20 cm layer (but sometimes shallower, i.e. top 0-10 cm or deeper to 0-40 cm, depending on the site). The land-use systems included anthropogenic sites managed with agricultural systems (e.g. pastures, annual and perennial crops, agroforestry), as well as planted forests and native vegetation located mostly in the southern Brazilian State of Paraná (96 sites), with a few additional sites in the neighbouring states of São Paulo (21 sites) and Santa Catarina (five sites). Important metadata on soil properties, particularly soil chemical parameters (mainly pH, C, P, Ca, K, Mg, Al contents, exchangeable acidity, Cation Exchange Capacity, Base Saturation and, infrequently, total N), particle size distribution (mainly % sand, silt and clay) and, infrequently, soil moisture and bulk density, as well as on human management practices (land use and vegetation cover) are provided. These data will be particularly useful for those interested in estimating land-use change impacts on soil biodiversity and its implications for below-ground foodwebs, ecosystem functioning and ecosystem service delivery., New Information: Quantitative estimates are provided for 42 soil animal taxa, for two biodiversity hotspots: the Brazilian Atlantic Forest and Cerrado biomes. Data are provided at the individual monolith level, representing sampling events ranging from February 2001 up to September 2016 in 122 sampling sites and over 1800 samples, for a total of 83,085 ocurrences., (George G. Brown, Wilian C Demetrio, Quentin Gabriac, Amarildo Pasini, Vanesca Korasaki, Lenita J. Oliveira, Julio C.F. dos Santos, Eleno Torres, Paulo R. Galerani, Dionisio L. P. Gazziero, Norton P. Benito, Daiane H. Nunes, Alessandra Santos, Talita Ferreira, Herlon S. Nadolny, Marie L. C. Bartz, Wagner Maschio, Rafaela T. Dudas, Mauricio R. G. Zagatto, Cintia C. Niva, Lina A. Clasen, Klaus D. Sautter, Luis C.M. Froufe, Carlos Eduardo S. Seoane, Aníbal de Moraes, Samuel James, Odair Alberton, Osvaldino Brandão Júnior, Odilon Saraiva, Antonio Garcia, Elma Oliveira, Raul M. César, Beatriz S. Corrêa-Ferreira, Lilianne S. M. Bruz, Elodie da Silva, Gilherme B. X. Cardoso, Patrick Lavelle, Elena Velásquez, Marcus Cremonesi, Lucília M. Parron, Amilton J. Baggio, Edinelson Neves, Mariangela Hungria, Thiago A. Campos, Vagner L. da Silva, Carlos B. Reissmann, Ana C. Conrado, Jean-Pierre D. Bouillet, José L. M. Gonçalves, Carolina B. Brandani, Ricardo A. G. Viani, Ranieri R. Paula, Jean-Paul Laclau, Clara P Peña-Venegas, Carlos Peres, Thibaud Decaëns, Benjamin Pey, Nico Eisenhauer, Miguel Cooper, Jérôme Mathieu.)