中文摘要：

本文利用X射线衍射法和自编的软件对杉木的微纤丝角进行了测定，结果表明：微纤丝角受很强的遗传控制，在不同株间、幼龄材间及成熟材间的差异极不显著；微纤丝角受树木生长年龄的影响很大，近髓心处最高，自髓心向外迅速减小，9a以后减小趋势缓慢，到大约15a时出现最小值，最大值与最小值相差达20多度，回归分析得到的二项式方程R^2达到0．899，径向各年轮间的差异极其显著；纵向不同高度上，微纤丝角从0m到1．5m迅速减小，之后减小趋于缓和，在5．5m以后于平稳波动中又略显回升，1．5～7．5m平均微纤丝角变化范围在10．82°-12．57°之间，回归分析得到的乘幂方程R^2达到0．884，方差分析表明，树高1．5m到7．5m微纤丝角差异不显著。

英文摘要：

The microfibril angles of six Chinese Firs were measured by using the X-ray diffraction and software programmed by the authers. The results showed as follows. The microfibril angle was controlled strongly by inheritance, so there were no significant differences in microfibril angle among interspecies, juvenile wood and mature wood. The ages of the trees had an important influence on microfibril angle, consequently, the microfibril angle differences were extremely remarkable in radial direction in different annual rings, which was maximal near pith and reduced rapidly from the pith to outside, and its reducing tendency were slow after the ninth year, to about the 15th year appeared as minimum value, the difference reached to more than 20° between the value of maximum and minimum, binomial equation＇s R^2 which .was gained by regression analysis achieved to 0.899. In longitudinal, the microfibril angle decreased rapidly from 0 to 1.5m, and then its reducing tended to relaxes, lastly, it would rise slightly under steady undulation after 5.5m, the variation range were between 10.82° and 12.57° from 1.5m to 7.5m, the R^2 of power equation achieved to 0. 884, variance analysis indicated that the microfibril angle variation werent remarkable from 1.5 to 7.5m.