We inve
stigated immediate, medium and long-term effects of logging on arboreal lichen biomass in old-growth balsam fir fore
sts (
Abies balsamea (L.) Mill.) in the highlands of Qu
xe9;bec's Gasp
xe9; Peninsula using three complementary approaches. Fir
stly, we e
stimated the immediate loss of lichen biomass following logging and the annual lichen litterfall from remnant trees over 2 po
st-logging years. Treatments included selection cutting at three intensities (25, 30, 35%), diameter-limit cutting and cutting with protection of regeneration and soils (CPRS). Among
studied treatments, we found that CPRS and diameter-limit cutting removed almo
st all the
standing lichen biomass, while selection and partial cut allowed an immediate retention of
40–60%of the initial lichen biomass. Our results also sugge
sted that the impact of logging on lichen litterfall rates were higher in silvicultural treatments (3–8.5%) compared to controls (1–2%); litterfall rates did not differ after 1 or 2 years po
st-treatment. Secondly, we evaluated medium-term effects by comparing pre-harve
st fruticose lichen biomass data with data collected at the same site 4 years after experimental thinning operations. Mean fruticose lichen biomass did not change 4 years po
st-harve
st. However,
Bryoria spp. biomass did increase relative to
Alectoria sarmentosa while
Usnea spp. remained unchanged. Finally, the long-term logging effects were assessed by evaluating fruticose lichen biomass along a fore
st chronosequence in
stands aged 30, 50, 70 and 90 years. Lichen biomass increased as a function of time for all genera, especially
Alectoria. Logging activities result in direct losses of lichen biomass, but careful selection cutting that retains large lichen bearing trees and maintains po
st-harve
st conditions not detrimental to lichen growth, particularly for
Bryoria spp., can ensure a sub
stantial biomass of lichens po
st-harve
st. Such measures may ultimately contribute to maintaining woodland caribou herds that rely on arboreal lichens.