Partitioning of Environmental and Taxonomic Controls on Brazilian Foliar Content of Carbon and Nitrogen and Stable Isotopes

The Neotropics harbor some of the most diversified woody species in world, and to understand nutrient dynamics these ecosystems, it is crucial role plant taxonomy. In addition, biological nitrogen (N) fixation (BNF) tropics one key processes affecting global N cycle. Our objective was (i) investigate taxonomy sampling site as predictors foliar carbon (C) concentration its stable isotopes (i.e., δ 13 C 15 N); (ii) assess differences N, C:N ratio, among three functional groups: 2 -fixers non-fixers Fabaceae family, well non-Fabaceae species; (iii) examine effect wood density on tree properties. We hypothesized that specimens symbiosis with would possess a higher than non-fixing plants, including those high-density trees have ratio relative low-density trees, where latter invest nutrients instead structural C. used data set composed 3,668 sampled main biomes Brazil: Amazon, Atlantic Forest, Cerrado. partitioning variance had influence leaf C, ratio. Conversely, were environmentally constrained. While family important level for played major N. Foliar followed pattern fixers > non-Fabaceae, while an opposite trend. correlated density, medium-density woods. large variability observed species, demonstrates complexity using indicator BNF. support hypothesis N-demanding lifestyle inherent this family. Lastly, although studies, prediction properties challenging, future research topic needed.