Impact of distance to mature forest on the recolonisation of bryophytes in a regenerating Tasmanian wet eucalypt forest

Abstract

Forest influence is a type of edge effect that occurs when mature forests affect the recolonisation of adjacent disturbed areas. This can be driven by changes in microclimate conditions near the edge or by an increase in establishment ability with proximity to a propagule source. Bryophyte recolonisation is sensitive to both microclimate and dispersal distance, therefore they are an ideal group to examine how strong forest influence is and over what distance it operates. Responses to forest influence are known to be highly species dependent; therefore, we tested whether distance affects the recolonisation ability of a range of bryophytes. As well as examining a range of species, we tested whether forest influence operated differently on two types of substrate used by bryophytes (logs and ground). For most of the species examined, establishment rates in disturbed forest diminished further away from the mature edge. The influence of unlogged mature forest on bryophyte establishment in harvested forest occurred up to 50 m. Species varied in their response to distance, and the relationships with distance were stronger on the ground compared with log substrates. These results support the concept of forest influence, with areas closer to mature forest experiencing more substantial re-establishment. These findings are relevant to conservation of bryophytes in managed native forests.