Fortschritte in der Floristik der Schweizer Flora (Gefäßpflanzen)

As part of the Biodiversity Monitoring Switzerland (BDM), comprehensive records of vascular plant species are made along 2.5-km transects and on 10-m(2) 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-m(2) 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.