Sampling multi-scale and multi-taxon plant diversity data in the subalpine and alpine habitats of Switzerland : report on the 14th EDGG Field Workshop

The 14th EDGG Field Workshop took place from the 4th to the 14th of September 2020 in Switzerland, and was devoted to the vegetation of open habitats in the subalpine and alpine zones. In total, 26 EDGG Biodiversity Plots (nested plots with grain sizes of 0.0001 to 100 m²) were sampled in different open habitat types (grasslands, heathlands, screes, snowbeds, fens) in three regions of Switzerland, both over acidic and base-rich bedrock. Additionally, three normal plots of 10 m² were sampled in high-elevation Festuco-Brometea stands in Zermatt. Across all grain sizes, stands showed 10–25% higher means and 50–94% higher maxima for total richness of vascular plants, terricolous bryophytes and lichens compared with data from the 12th EDGG Field Workshop in dry and semi-dry grasslands of the central valleys of the Swiss Alps. We found outstanding preliminary maxima of total richness of 61, 109 and 163 species in 1, 10 and 100 m² respectively, in an unused alpine grassland over limestone (Seslerion). Both particularly variable and partly extremely rich was the bryophyte and lichen flora of the analysed stands, with up to 33 bryophyte and 22 lichen species in 10-m² plots. We report the liverwort Cephaloziella dentata as new for Switzerland, found in a thermophilous subalpine heathland at Alp Glivers, Surselva, Grisons. Overall, our preliminary data suggest that some of the sampled subalpine and alpine habitats are among the most species-rich communities at small scales if bryophytes and lichens are also considered. Based on this finding, we recommend that these two taxonomic groups be more regularly included in surveying and particularly in monitoring programs for vegetation. The Scientific Report is supplemented by a photo diary that provides impressions of work and life during the Field Workshop