The decrease of rich fen bryophytes in springs as a consequence of large-scale environmental loss. A 50-year re-sampling study
Riikka JuutinenR. Juutinen (firstname.lastname@example.org), The Centre of Excellence in Evolutionary Research, Dept of Biological and Environmental Science, PO Box 35, FI–40014 University of Jyväskylä, Finland.
As sensitive indicators of environmental change, many bryophytes are particularly threatened by the degradation of habitats. A long term re-sampling study of bryophyte flora was conducted in springs in southeast Finland, in which the species occupancy and abundance, as well as the degree of human disturbance, of 60 springs were reinvestigated after a period of 50 years. A significant decrease was observed in the spring specialist species’ occupancy and abundance, and bryophytes of spring-fed rich fens were found to have become regionally even rarer and locally less abundant than other spring specialists. The negative reaction of least concern (LC) species raises concern regarding the future of even common spring and rich fen bryophytes. The increase of human disturbance was found to poorly explain the observed negative changes and it was inferred that they are mainly caused by the almost total destruction of springs with rich fen characteristics. Thus, the protection of groundwater influenced rich fens independent of their degree of human disturbance is essential to the future of many specialized spring bryophytes.