Based on 29 stems analysis and 140 sample trees of nature Korean pine (Pinus koraiensis Sib.et Zucc.) measured on the Xiaoxing'an Mountain, effects of age ranged from 20 to 300 years on stem form were discussed a...Based on 29 stems analysis and 140 sample trees of nature Korean pine (Pinus koraiensis Sib.et Zucc.) measured on the Xiaoxing'an Mountain, effects of age ranged from 20 to 300 years on stem form were discussed and a compatible taper and volume ratio system was developed. The merchantable cubic-metre volume ratio table of varying log rules was constructed for nature Korean pine in this paper. Results indicated that age classes were regarded as a totality to develop taper equation. The compatible tree profile and volume ratio equation developed in this paper can be used to obtain estimates of individual tree volumes and stem profile or volume of varying merchantability limits.展开更多
The study involved estimating stem volume, calculating merchantable volume yielding rate and timber assortments volume with four parameter cylinder volume ratio stem profile. The result shows it performs better than S...The study involved estimating stem volume, calculating merchantable volume yielding rate and timber assortments volume with four parameter cylinder volume ratio stem profile. The result shows it performs better than Schumarher Hall at estimating stem volume when the data from Quercus aliena were classified by class. Compared with taper function at calculating merchantable volume yielding rate, four parameter cylinder volume ratio stem profile also performs well with systematic error below 1% and mean square error below 5%. To Pinus tabulaeformis trees, taper function has better accuracy degree than cylinder volume ratio method, but the result is contrary to Q.aliena. When calculating timber assortments volume with four parameter cylinder volume ratio method, systematic error is below 6% and mean square error below 19%.展开更多
文摘Based on 29 stems analysis and 140 sample trees of nature Korean pine (Pinus koraiensis Sib.et Zucc.) measured on the Xiaoxing'an Mountain, effects of age ranged from 20 to 300 years on stem form were discussed and a compatible taper and volume ratio system was developed. The merchantable cubic-metre volume ratio table of varying log rules was constructed for nature Korean pine in this paper. Results indicated that age classes were regarded as a totality to develop taper equation. The compatible tree profile and volume ratio equation developed in this paper can be used to obtain estimates of individual tree volumes and stem profile or volume of varying merchantability limits.
文摘The study involved estimating stem volume, calculating merchantable volume yielding rate and timber assortments volume with four parameter cylinder volume ratio stem profile. The result shows it performs better than Schumarher Hall at estimating stem volume when the data from Quercus aliena were classified by class. Compared with taper function at calculating merchantable volume yielding rate, four parameter cylinder volume ratio stem profile also performs well with systematic error below 1% and mean square error below 5%. To Pinus tabulaeformis trees, taper function has better accuracy degree than cylinder volume ratio method, but the result is contrary to Q.aliena. When calculating timber assortments volume with four parameter cylinder volume ratio method, systematic error is below 6% and mean square error below 19%.