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Thermal limits of tree species are of paramount interest in monitoring and projecting effects of climate warming. Based on the large phytosociological database BERGWALD, a database of forest inventory plots, and phytosociological tables of vegetation above treeline, tree species occurrence along a regional elevation gradient was assessed separately for tree and regeneration layer individuals. Upper limits in the database were compared to altitudinal limits given in Oberdorfer’s regional flora and to northern latitudinal limits given in worldwide distribution maps. For 26 of 32 tree species, the known distribution limits had to be raised based on plot data, demonstrating the high potential of vegetation databases to deliver ecological information. In most species, regeneration layer occurrences markedly exceeded the altitudinal limit of trees, indicating a potential for rather rapid advances of treelines under climate warming. Regional altitudinal and global latitudinal limits were quite closely related in the majority of tree species. However, several tree species climb to much higher elevation in the Alps than their latitudinal limits suggest. The boreal-subalpine mismatch in cold limits is only partly explained by vicariism and endemism. Sorbus aria, Acer pseudoplatanus, Fagus sylvatica and Taxus baccata are important elements of temperate mountain forests, which do not reach thermally equivalent northern latitudes for unknown reasons.

In 2010, we launched the Global Index of Vegetation-Plot Databases (GIVD; http://www.givd.info), an internet-based resource offering metadata of existing electronic vegetation databases. On 11 May 2012, 182 databases containing more than 2.8 million non-overlapping vegetation plots had been registered in GIVD. The majority of these plots were from European databases (123 databases, 1.87 million plots). The oldest plot record dated from 1864, but the vast majority of the plots had been collected since 1970. Most of the plots had areas between 1 and 1,000 m2. A total of 68 databases also stored time series and/or nested-plot data. The vegetation-plot data registered in GIVD constitute a major resource for biodiversity research, not only through the large number of species occurrence records, but especially due to the storage of species co-occurrence information, complemented with site-specific structural data and plot-based environmental data. The increased ease of discovering and accessing such datasets, owing to their registration in GIVD, offers significant opportunities for large-scale studies in areas such as community ecology, macroecology, and global-change research. The results from such studies could be very important for nature conservation practice and policy.

The database BERGWALD (GIVD ID EU-DE-002), an electronic repository for vegetation plot data from forests and related vegetation in the Bavarian Alps (Germany), is presented. Created in 1995, the database has been intensively used for the classification and mapping of vegetation and site types, for calibrating and evaluating plant indicator values, and for analysing patterns of plant species richness. Hosted at the University of Applied Sciences in Freising, Bavaria, the data are available for collaborative re

WINALPecobase (GIVD ID EU-DE-003) is an ecological database of mountain forest plots in the Bavarian Alps (Germany). Created in 2009, the database features the following characteristics: (1) 1,505 georeferenced forest releves with concomitant soil profile descriptions, (2) placement across the whole study area (ca. 4,600 km2) according to a design that combines systematic and stratified sampling, (3) consistent standards for vegetation and soil inventory, and (4) extensive quality control of the database. The database is available for collaborative research.

VegetWeb (GIVD ID EU-DE-013) is an online archive for vegetation-plot data from Germany and can be accessed at the FloraWeb website of the Federal Agency for Nature Conservation (http://www.floraweb.de). The data model of VegetWeb allows upload, storage and interactive search of plot data with different original formats and taxonomic reference. Due to financial constraints only a small proportion of Germany's legacy of plot data has been captured so far. VegetWeb co-operates with the journal Tuexenia, for which it provides an interactive online archive of releve tables by capturing and distributing all newly published data.