Mean (N = 3) N2 fixation rates (nmol C2H2 g−1 dm bryo. h−1) cyanobacteria abundance (nmol echinenone/bryophyte cm2) and cyanobacteria genera associated with each individual bryophyte species along both glacier chronosequences.

In both glaciers the younger site (site 1) correspond to early succession site close to the glacier front whereas the older site (site 5) was settled within Nothofagus forests. Sites 3–4 represent intermediate stages of ecological succession. No species were sampled at site 0. SE for cyanobacteria abundances is shown in brackets. NG: north-side glacier; SG: south-side glacier of the mountain range.