Biomass Growth in Five Alectorioid Lichen Epiphytes

Biomass growth in alectorioid lichens was measured during one year by repeated weighing technique. Five pendent lichens were transplanted to a mature Picea abies forest and suspended in netting cages. The change in biomass with time was substantially affected by thallus fragmentation in all species except Usnea filipendula. The highest annual growth rate for unfragmented thalli was found in U filipendula (16.3% ), followed by Alectoria sarmentosa (11.5% ), U longissima (9.2 % ), Bryoria fuscescens (8.6%) and B. fremontii (6.3% ). Maximum growth of individual thalli ranged from 11 % in B. fremontii to 40% in Alectoria sarmentosa. The study shows that lichen transplants can be used to measure biomass growth in alectorioid species. The results suggest that some alectorioid lichens possess a considerable growth potential and that the extent of thallus fragmentation strongly influences the pattern of biomass accumulation. The method should have wide application in ecological and biomonitoring studies, for example, to follow the vigour of transplants of threatened lichen species.