Estimation of lichen biomass with emphasis on reindeer winter pastures at Hardangervidda, S Norway

Quantification of lichen abundance is important for management of reindeer populations. We measured dry lichen biomass in 876 micro plots (16.5 cm × 16.5 cm) systematically sampled within 219 vegetation plots (2 m × 2 m) from 7 different areas in S Norway. Lichen biomass was quantified as: (a) dry weight in g m-2, (b) lichen height in cm, (c) lichen cover, and (d) lichen volume (lichen height × lichen cover). Lichen biomass decreased with increasing precipitation and increasing altitude. On local scale, the variation in lichen biomass varied strongly with snow conditions. The grazed parts of Hardangervidda had in general a low average lichen biomass (an average mostly lower than 150 g m-2). Lichen biomass was much higher in area where reindeer migration was interfered by human activity. Lichen height and lichen volume were strongly linearly correlated with dry lichen biomass. These proxy methods may therefore be used to predict lichen biomass, but deviations from exact measurements should be expected.