Czech Vegetation Database: an open source of vegetation-plot data for research and applications

The Czech Vegetation Database (formerly Czech National Phytosociological Database) was founded in 1996 as a national electronic archive of vegetation-plot data. Throughout its history, it has provided data for research and applications to multiple users. In 2026, the entire database was published online as an open resource. This article describes the published open datasets. The dataset CzechVeg-Open 1 contains 117,739 vegetation-plot observations (i.e., records of species composition from vegetation plots, also called relevés) from the territory of the Czech Republic. It is provided in two formats, as Turboveg 2 files and CSV files. This dataset can be explored in the CzechVeg-DataViewer, an interactive online application developed with the shiny package in R. The dataset CzechVeg-OpenStrat 1 contains a subset of 61,282 vegetation-plot observations, which is more balanced in terms of plot density in different areas and habitat types and is better suited for national-level statistical analyses. It was prepared using an original resampling method that applies thresholds on spatial distance and species-compositional similarity between plot observations. Resampling was applied within strata defined based on principal component analysis (PCA) of 18 environmental variables. Both datasets are published and described on the database website at https://czechveg.github.io and in the Zenodo repository. In addition, the database has been published in GBIF (Global Biodiversity Information Facility), where it currently includes 2,481,138 species records. Species records from individual plot observations are grouped as Sampling events as defined by the Darwin Core standards for sharing biodiversity data. In addition to the data, the database website includes instructions for data digitization using the Turboveg 2 program and a tutorial on data handling and analysis in R with code chunks. These resources can be used to train the analysis of vegetation-plot data and to prepare open and stratified-resampled versions of other vegetation-plot databases.