V. Valtchev et V. Nikolov, PRIMARY PRODUCTION OF A BLACK PINE ECOSYS TEM (PINUS-NIGRA ARN) IN THE RESERVE TCHERVENATA-STENA, IN BULGARIA, Belgian journal of botany, 126(2), 1993, pp. 164-174
A plant community of Pinus nigra Arn. with a 70-80 years old stand was
investigated. The aboveground phytomass of the stand was 278 t/ha. Th
e stem biomass was increased with 23,6 t/ha every 5 years (dry weight)
. The litter fall per year was 3,5 t/ha. The mean value of the ground
layers production was reached to 897 kg/ha/y. The whole aboveground ph
ytomass in the community was 282,3 t/ha.