As part of the Biodiversity Monitoring Switzerland (BDM), comprehensive records of vascular plant species are made along 2.5 km transects and on 10 m2 plots distributed regularly over the entire surface of Switzerland (www.biodiversitymonitoring.ch). Here we analyse data from 2001-2003 for 275 transects and 773 plots (70 287 floristic records). A comparison with the distribution atlas of vascular plants (based on data from 1982-1994) shows that 3 481 records of indigenous taxa from the BDM were new, i.e. species that had not been found in the corresponding mapping unit previously. Alien species (mostly of non-European origin) represented 2.11% of the 2.5-km transect records and 1.01% of the 10-m2 plot records. Red list species (critically endangered, endangered or vulnerable) represented 0.26% of the transect records and 0.06% of the plot records. These percentages are low, given that in 2002, the Swiss flora included 17.5% of alien species and 31.5% of red list species. In accordance with its purpose and methodology, the BDM mainly shows the distribution of widespread species, whereas other monitoring approaches are needed for rare species.

Bäumler, B.; Moser D.M.; Gygagx, A.; Latour, C.; Wyler, N. (2005). Fortschritte in der Floristik der Schweizer Flora (Gefässpflanzen). 69. Folge (Vergleiche des Verbreitungsatlas mit den ersten Daten 2001-2003 des Biodiversitätsmonitoring Schweiz). Botanica Helvetica 115: 83-93.