Biomass partitioning of beech seedlings under the canopy of spruce

摘要

We examined the development of beech seedlings below the canopy of a mature spruce stand on experimental plots. On two sites in southern Germany (Bavaria) 249 seedlings which had been sown were harvested in autumn 2004. At the time of the harvest, theseedlings were therefore eight years old. All seedlings were divided into three compartments (main stem axis, branches and roots), which were dried to constant weight. In 1997, 1998, and 2003, the stem length (in mm), the stem diameter 3 cm above ground(in mm~(-1)) and the first order branch number of each seedling had been determined. The results indicated that there are two traits in the biomass partitioning of the seedlings, one related to size and the other one related to resource availability. The bigger the seedlings were and the stronger the seedlings competed for light, the lower the root fraction and the higher the shoot-root-ratio. The findings indicate how important intraspecific competitive interactions between seedlings are for their growth response and biomass partitioning even in very early stand phases.