Bryophyte flora and vegetation of managed and virgin coniferous forests in South-West Sweden

Abstract

One virgin and three managed Picea abies stands in SW Sweden were investigated and their bryophyte flora and vegetation compared. The composition of the bryophyte vegetation did not differ much between the stands. Cover of the single dominant species was very similar. Most common species were Pleurozium schreberi, Dicranum majus, D. polysetum, Sphagnum girgensohni and Hylocomium splendens. Species number and total cover was somewhat higher in the virgin stand (88 species, 73% total cover) than in the managed stands (56–72 species, 49–59% total cover). The diversity (Shannon-Wiener) ranged from 2·3 to 2·9. The importance-value curve for all stands taken together was intermediate between lognormal and geometric in shape. Rare hepatics growing on large logs, such as Calypogeia suecica, Odontoschisma denudatum and Scapania umbrosa, distinguished the virgin stand from the managed stands. Such uncommon log-species are threatened if intense, full-scale forestry continues. Large coniferous forests should be protected if they are to survive. Consideration should be given to the bryophytes when forestry is conducted; large logs should be allowed in a stand, forest fens should be left undrained, and areas with old trees left when clearcutting.