南带产区不同立地类型间的杉木木材解剖

为了解不同立地类型杉木木材解剖上的差异,为杉木速生材的定向培育及材质改良提供更为充分的理论依据,该文采用宏观、微观的方法,以广西国营高峰林场12～13年生的杉木木材为试材,于2001—2003年研究了南带产区不同立地类型(南坡、山谷、山脊、山顶)间杉木木材解剖上的差异. 结果表明:①生长轮宽度及晚材率差异显著. 生长轮宽度径向变异随着年龄的增加呈先增加后减小的趋势,纵向变异随着高度的增加呈先增大后减小的趋势. 而晚材率的径向、纵向变异规律均不明显. ②管胞双壁厚及壁腔比差异显著,而长度、宽度、长宽比差异不显著. 各解剖因子径向变异模式相似,而纵向变异规律较为复杂.③微纤丝角差异不显著. 径向变异均为随着年龄的增加而减小,纵向变异呈“大—小—大”的模式. ④组织比量差异不显著. ⑤气干密度差异显著. 

Wood anatomy of Chinese fir in different site types of its southern growing district

In order to investigate the differences of wood anatomy of Chinese fir (Cunninghamia lanceolata(Lamb.) Hook) among different site types and to provide more theoretical instructions for cultivating fast_growing wood and improving wood properties, this paper discusses wood anatomic characteristics of Chinese fir obtained from southern slopes, mountain valleys, mountain ridges and mountain tops from 2001 to 2003 The samples come from 12～13_year_old trees in Gaofeng Forestry Center in Guangxi Zhuang Autonomous Region. The macroscopic and microscopic methods are employed. The research results show that: 1) There are significant differences in both growth ring width and latewood percentage among different site types. The growth ring widths of four site types increase at first and then decrease with an increase of age in a radial direction. The same trend is observed with increasing height in a longitudinal direction. However, there is no obvious trend in the changes of latewood percentage in both radial and longitudinal directions. 2) The differences in thickness of the cell wall and the ratio of cell wall to cavity are significant, while the differences in tracheid length, width and ratio of length to width are insignificant. Their radial variations are similar, but longitudinal variations vary with site types. 3) The differences of microfibrillar angle among different site types are not noticeable. It gradually decreases with the increase of ages in radial variation. But in a longitudinal direction, it appears as “big_small_big" with an increase in height. 4) The differences in proportion of wood tissues are insignificant. 5) There are marked differences in air_dried density.