Biomass production and productivity in oak forests of the Eastern Carpathians in relationship with stands age

The results of the biomass production and productivity study of oak forest ecosystems in the Eastern Carpathians are presented. On the basis of data o n structure and productivity of oak (Quercus robur L.) forests of different age (33,54, 75, 106 years old) in the Eastern Carpathians, the biomass flu ctuation in the range of 120.5 - 239.8 t ha(-1) (dry weight) was found. Mas s of stems and roots varied in the range of 66.9 - 146.5 and 27.9 - 45.4 t ha(-1) respectively. The annual increment of biomass was 10.1 t ha(-1)year( -1) in 106 years old and 14.0 t ha(-1)year(-1) in 33 years old oak forests The ratio between the mass of leaves to mass of thin roots for the sampling areas was 3.5 - 4.0. Leaf area index changed from 4.3 ha ha(-1) in the 33 years old oak forest stand to 3.3 ha ha(-1) in 106 years old stand. Total l eaf area index for tree and shrub layer changed from 7.3 to 4.2 ha ha(-1) r espectively. The leaf area index decreased with age of the oak forests. The results will be used to estimate realistically the potential biomass produ ction and productivity of oak ecosystems in the Eastern Carpathians.