Dependence of bryophyte species on young, mature and old growth wet eucalypt forest

Maintenance of old growth forest has been argued to be important for the future of many bryophyte species, but there has been no empirical test of this proposition. Bryophytes constitute much of the plant biodiversity in Tasmanian tall open-forests dominated by Eucalyptus regnans and Eucalyptus obliqua. These forests have a low level of protection in their old growth stage. We ask whether if there is a concentration of bryophyte species in particular forest age classes and assess its significance for biological conservation. The bryophyte species at 99 forest sites were recorded and related to young, mature and old growth age classes using ANOVA. Only two bryophyte taxa were confined, with statistical confidence, to one of these classes. Succession in bryophyte assemblages takes the relay floristics form, with a few highly frequent species in the young forest, most of which do not persist in later stages, a large number of species establishing in middle-aged forests, some dying out with their short-lived hosts by the time of the old growth forest stage, and liverworts becoming more prominent with age. Species concentrated in the old growth phase of these eucalypt forests have all been recorded from secure reserves in this and other vegetation types. If present patterns of land use continue, and no extensive wild fires occur in the reserved old growth forest, almost all bryophyte species of E. regnans and E. obliqua mixed forest are likely to survive. This may not be the case in other regions of the world, where reservation may be poorer than in Tasmani