Maps of mean relative species richness of vascular plant families in European vegetation

This set of maps shows the representation of 152 vascular plant families within forest, grassland, scrub and wetland plant communities across Europe. We used a set of 816,005 vegetation plots from the European Vegetation Archive (EVA; Chytrý et al. 2016), and for each plot, we calculated the relative species richness of individual plant families (number of species belonging to the family divided by the total number of species in the plot). The relative species richness was then mapped, averaged across all plots in 50 km × 50 km UTM grid cells, for each family and broad habitat groups – forests, grasslands, scrub and wetlands.

Here we provide the maps as (i) images (PDF files) and (ii) tables (XLSX files) containing the source data to be used for visualization in R or GIS software.

The colour scale in the maps was generated from the data using the k-means algorithm. For each map, the distribution of the values and the minimum, maximum and median values are shown. The maps only show grid cells containing at least five vegetation plots. Of these grid cells, those with mean relative species richness of the mapped family equal to zero are in grey. For each map, we also provide the number of genera/species included, the Shannon diversity index for the combination of the family and the habitat group, and the number of plots included (both absolute and relative to the total number of plots in the habitat group). The Shannon diversity index is based on species occurrences in vegetation plots: higher values indicate that the family is represented by many species with relatively even occurrence frequencies, while lower values indicate that it is represented by few species or some species is much more frequent than the others. For the combinations of families and habitat groups not represented in the dataset, blank maps were generated and the respective columns in tables filled with NAs. For further details, see Večeřa et al. (2021) Journal of Vegetation Science https://doi.org/10.1111/jvs.13035.

Contents:

• Families_maps_all.pdf – a file containing maps of mean relative species richness of all the families
• Families_maps_one-by-one.rar – separate files of individual families
• Families_attribute_table_data.xlsx – a matrix of mean relative species richness for vascular plant families (columns) in 50 km × 50 km UTM grid cells (rows) in forests, grasslands, scrub and wetlands (four sheets); a family is considered absent (the mean relative species richness equal to zero) only in grid cells containing at least five vegetation plots; grid cells with no data or containing less than five plots are marked NA.
• Colour_scale_codes.xlsx – a table of colours (HEX and RGB definitions) used for generating colour scales in the maps, with colour-scale codes (0–7) that may be used in combination with the file Families_attribute_table_colour-codes.xlsx to generate maps with the same colour representation as the original maps.
• Families_attribute_table_colour-codes.xlsx – a matrix of colour-scale codes representing eight classes of the mean relative species richness (columns) in 50 km × 50 km UTM grid cells (rows) in forests, grasslands, scrub and wetlands (four sheets). In combination with the file Colour_scale_codes.xlsx, this table enables to reproduce the maps with the original colour representation. A family is considered absent (colour-scale code equal to zero) only in grid cells containing at least five vegetation plots; grid cells with no data or containing less than five plots are marked NA.
• Europe_CGRS_grid.rar – a shapefile of the 50 km × 50 km UTM grid for Europe (originally available at: https://www.eea.europa.eu/data-and-maps/data/common-european-chorological-grid-reference-system-cgrs) to which data from the files Families_attribute_table_data.xlsx and Families_attribute_table_colour-codes.xlsx may be joined.