Above-ground biomass allocation in boreal drained Downy birch (Betula pubescens Ehrh.) dominated peatland sites

Stand biomass in boreal forests plays a crucial role in carbon cycling. In this study, we examined the effect of stand age on above-ground biomass allocation in downy birch (Betula pubescens Ehrh.) in three drained peatland sites in Central Finland. We used allometric equations to estimate individual-tree above-ground biomass and its various components, including stem wood, stem bark, living branches, leaves, and dead branches. The above-ground biomass ranged from 9.2 t ha-1 to 276.0 t ha-1 and foliage biomass from 0.008 t ha-1 to 0.6 t ha-1. We found that stand age had a strong correlation with above-ground biomass, but foliage biomass appeared to peak at the middle-age (50 years) stand compared to the young (10 years) or mature (80 years) stands. Our findings improve our understanding of how biomass allocation patterns change over time, specifically the changes in foliar biomass, and its impact on litter inputs into the soil.