The sample stand of Pinus rigida plantation was chosen from those at the Choongnam Forest Experiment Station, Choongnam. The diameter at breast height (D) and the height of tree (H) of each tree in the sample plot of 200㎡ were measured yearly a from 1967 through 1969. The stand was 12.7-13.4㎝ in mean diameter and had a stand density of 2,150 trees per ha. The trunk, branches and leaves of each sample tree were separately weighed according to the stratified clip technique. The allometric relation between D^2H and dry weight of trunk (Ws), branches (Wb) and leaves (Wl) were approximated by
Ws=0.05917 (D^2H)^(0.837)
Wb=0.O0655(D^2H)^(0.989)
Wl=0.04466(D^2H)^(0.690)
From the above, the standing crops in the sample stand was estimated to be as much as 76.7, 81.7 and 88.2 tons of dry matter, ahove ground, per ha in 1967, 1968 and 1969, respectively.
Annual net production, as the sum of the biomass newly produced during one year, was estimated at 4.97-5.47 tons per ha per year. The respiratory and the photosynthetic rate deduced from theoretical calculations were 0.045 and 0.74㎏ of dry matter per ㎏ per year. Tentative estimate of annual respiratory loss was made and annual gross production was roughly estimated at 4.4 - 4.7 and 10.7 - 12.9 tons of dry matter per ha per year. The ratio of respiratory loss to gross production was approximately 36 - 41:1.
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