POST-HARVEST BIOMASS STOCK AND PRODUCTIVITY OF CALAMAGROSTIS EPIGEJOS COMMUNITY UNDER BEECH AND SPRUCE FOREST STAND

We investigated the above- and below-ground standing biomass and production of plant communities dominated by bushgrass (Calamagrostis epigejos) colonizing forest clearings created by harvesting beech-spruce forest stands. Above-ground living biomass of these communities was 6.6 t.ha(-1), while above-ground litter made up 5.6 t.ha(-1). Below-ground standing biomass was 6.6 t.ha(-1) and production was 1.6 t.ha(-1). Inter-annual fluctuations in production were rather high and did not clearly follow weather alternations. We hypothesize about some of the reasons for this. A negative correlation between litter and production of bushgrass rhizomes and root were found. The amount of bushgrass above-ground biomass did not affect species' richness, but a higher amount of its roots inhibited occurrence of other species, especially other dominants in the forest clearings Epilobium angustifolium and Rubus idaeus. The bushgrass produced rhizomes mainly at micro-sites with higher proportions to other species. The number and average length of the bushgrass blades are related to its above-ground biomass. We conclude that the competition between bushgrass and other species takes place most heavily in the top soil layer. Biomass production of bushgrass communities is not sensitive to weather patterns under the conditions of beech-spruce forest clearings. In terms of the carbon accumulation and nutrient cycling, these communities have an important role in certain periods of forest life.