Aboveground biomass stocks and net primary production of three primeval European beech forests in eastern Slovakia

The study took place in three primeval European beech forest reserves in eastern Slovakia and in three close by production forests with similar site conditions. Three compartments of aboveground biomass stocks (live woody tree biomass, litter biomass, regeneration biomass, coarse and fine woody debris) and two compartments of aboveground net primary production (anual woody biomass increment and litter production) were inventoried. Stand structural data (tree diameter, coordinates, height and more) was inventoried on 40 500 m^2 plots per primeval forest and on 10 plots of the same size per production forest (low intensity plots - 150 LIPs in total). This data was used to estimate live woody biomass on basis of allometric equations. The structural data of the plots were used to classify the primeval forest plots into three stages of the natural development cycle (growth, optimal, terminal). The classification was used as a basis to select four plots per development stage and four plots per production forest for the recording of the remaining biomass and productivity compartments (high intensity plots - 48 HIPs in total). Litter biomass and production was estimated using litter traps. Regeneration biomass was recorded by counting regeneration trees on sub-plots of the 48 HIPs. Coarse woody debris was estimated by measuring dimensions of all downed logs with base diameters >= 20 cm. Fine woody debris was estimated with line intersect sampling on 4 6.5 m long transects per plot. Annual woody biomass was estimated by taking repeated readings of permanent increment tapes. Upscaling to tree level was done with allometric equations