摘要
基于杉木林分调查数据讨论了林分胸高形数η和径高比δ随林龄 t变化的相关性 .η和δ值均随 t递增而递减 ,且递减趋势相似 ,η/δ比值近似为常数 ;η和δ也随立地 S递增而递减 ,其比值在调查的 S范围内不随 S变化产生显著差异 ;η随林分密度 N递增而递增 ,δ随 N递增而递减 ,η/δ比值与 N成正相关 .在 t递增过程中 ,给定 S和 N ,η/δ比值变幅小是蓄积方程 Y=Ymt3/( K+t) 3应用精确度较高的主要原因 .
The correlation between the breast diameter height form factor η and the diameter height ratio δ with respect to the change in tree age t has been analyzed based on the data obtained from China fir forests. Both η and δ decrease with increasing t with similar trends, thus keeping the η/δ ratio nearly constant. These two factors also decrease with increasing site index S and their ratio does not change significantly within the S level range investigated. The η factor increases while the δ factor decreases with increasing stand density N , leading to a positive correlation between the η/δ ratio and N . Accounted for by the insignificant variation of the η/δ ratio with increasing t giving S and N , the stand volume growth equation, Y=Y mt 3/(K+t) 3 ,gives relatively high accuracy in application.
出处
《中南林学院学报》
CSCD
2000年第1期1-6,共6页
Journal of Central South Forestry University
基金
国家“八五”林业科技攻关专题“工业用材林施肥技术和地力维护措施研究”和“九五”林业科技攻关专题“纸浆材微生物应用与施肥技术研究”的部分内容。
关键词
杉木
胸高形数
径高比
立地条件
林分密度
蓄积方程
China fir
breast diameter height form factor
diameter height ratio
site quality
stands density
stand volume growth equation.
