Biomass and composition of understory vegetation and the forest floor carbon stock across Siberian larch and mountain birch chronosequences in Iceland Bjarni D. Sigurdsson, Borgthor Magnusson, Asrun Elmarsdottir and Brynhildur BjarnadottirAnn. For. Sci., 62 8 (2005) 881-888DOI: https://doi.org/10.1051/forest:2005079