2007 Volume 18 Issue 5 Pages 350-355
The present study investigates the moisture content of stem and woody biomass evaluation in logs with small diameters obtained from the first thinned 26-year-old Sugi (Cryptomeria japonica D. Don) seedling plantation in a standine with varying slopes. The standine was classified into three slopes : the lower part characterized by a flat slope ; the middle part with a moderate slope ; and the upper part with a steep slope. A comparison of moisture content in the stem and woody biomass accumulation was performed among samples from the three plots. The average wood density in the oven-dried condition and moisture content of the stems were at 0.31 ton/m3 and 66.2%, respectively. Statistical differences in wood density, and moisture content of the stems among the samples from the three plots were determined by an analysis of variance. Both traits were found to be of no significance among the three plots. Moisture content of the stems was found to have no correlation with the diameter at breast height (DBH), while woody biomass accumulation showed a good, positive significant correlation with DBH. Woody biomass accumulation from thinned logs ranged from 26.60 to 36.69 ton/ha with average 31.30 ton/ha. In addition, the woody biomass amount showed a trend to increase from the upper plot to the lower plot. Thus, moisture content of the stems shows an independent trait, from DBH and plot. Results indicate that woody biomass can be evaluated from a stem-radial growth of the trees, irrespective of plots with different slopes.
