sPlot – the global vegetation-plot database

Vegetation-plot databases contain biodiversity data on presence and relative abundance of plants co- occurring in the same community. Compared to databases based on occurrence records of individual species aggregated at the level of grid cells, vegetation-plot databases have the advantage of providing information on species relative cover, co-occurrences, and to provide more reliable information on true absences. Although large collections of plant community data are now available at national to regional level, they are rarely accessible at continental or global extents, as their compilation is technically and conceptually challenging, due to different data formats and taxonomical nomenclatures used. Here we present the sPlot database, which merges and standardizes data contributed by more than 100 regional, national and continental databases, and contains records from 1,121,244 vegetation plots, for a total of 23,586,216 plant species entries with relative cover or abundance. All plots are georeferenced, although with varying precision, their size varies from less than 1 m 2 to 25 ha, and span from year 1885 to 2015. The vegetation-plot data are stored in a SQLite database, managed with TURBOVEG v3 software, and further processed in R for data integration and analysis. In order to make sPlot suitable for the exploration of global patterns in taxonomic, functional and phylogenetic diversity at the plant community level we performed three steps. 1) We standardized the species lists of the different databases in sPlot through the construction of a taxonomic backbone using existing databases on accepted plant species names. 2) We calculated functional attributes of each plot (community-weighted means and variances of traits) using gap-filled data from the global plant trait database TRY. 3) We generated a phylogeny for 50,167 out of the 54,519 vascular plant species occurring in sPlot. Finally, in addition to the information provided by the data owners, we retrieved for each plot information on environmental conditions (i.e. climate, soil) and the biogeographic context (i.e. biomes) from external sources. sPlot provides a unique, integrated global repository of data that would otherwise be fragmented in unconnected and structurally inconsistent databases at national or regional level. We believe that sPlot can be the basis for a new generation of studies, not only to address fundamental ecological questions related to plant diversity patterns or community assembly rules, but also to foster further development and testing of macroecological theories and as an information baseline for refining interdisciplinary conservation studies in a human-dominated, changing world. Further information: https://www.idiv.de/en/sdiv/working_groups/wg_pool/splot.html