在浙、闽2省选取成一定纬度和海拔梯度的6个木荷天然林分,开展树干形质、树皮形态、木材纹理扭曲度、木材颜色和基本密度等个体类型表型变异及产地纬度和海拔影响研究。结果表明: 木荷天然林分个体树皮厚度、颜色、形状及木材颜色等类型多样,除木材纹理扭曲度外,树干形质、树皮形态和木材基本密度等在林分间存在显著表型差异,但在林分内个体间变异以木材纹理扭曲度最大,树干圆满度、通直度和木材基本密度最小。木材性状的径向变异研究发现: 木材基本密度由髓心向树皮方向逐渐下降,而年轮则先变宽后变窄,15~25年轮为平稳生长期。较高纬度的天然林分其树干相对通直圆满、树皮较薄、木材颜色较浅,而其他性状则未呈现明显的规律性; 随海拔升高,木荷天然林分具有树干圆满、树皮薄而光滑,但树干通直度低、年轮窄、木材基本密度小的变化趋势。基于中心产区2个不同海拔天然林分个体性状相关分析表明,性状相关因林分所处海拔不同而有较大差异。在高海拔林分中,树皮性状是材性和径生长较好的指示指标,树干圆满的个体树皮光滑且颜色较浅、木材基本密度较小,而树干越通直的个体,树皮颜色越深,径生长也越快; 在低海拔林分中,树皮厚度对树皮的其他性状和木材密度也有较好的指示作用,树干通直、树皮颜色浅、径生长量大的个体其木材纹理扭曲度较小、木材基本密度增大。
Six natural stands of Schima superba with latitude and elevation gradient were selected in Zhejiang and Fujian Provinces to study individual phenotypic variation in stem form,bark morphology and wood properties, as well as effect of latitude and elevation on these traits. The purpose of our experiment was to provide a theoretical basis for the further exploitation and utilization of within-species variation of S.superba. The results revealed various types of bark traits and wood color among natural stands of S.superba. There were significant differences in stem form, bark type and wood basic density, but not in wood texture distortion degree among different stands. In contrast, the largest within-stand variation in wood texture distortion degree and the lesser within-stand variation in stem fullness, stem straightness and wood basic density were observed. Radial analysis in wood property showed that wood basic density decreased from pith to bark gradually. The ring width was increased at first but followed by reduction, and remain constant during 15th to 25th rings. Results also demonstrated that natural stands from higher latitudes exhibited higher stem fullness and straightness, thinner bark and lighter wood color relatively, whereas no clear regularity were observed for other characters. The effect of elevation was more significant in comparison with latitude, as increased trunk fullness, thinner and smoother bark, as well as decreased trunk straightness, ring width and wood basic density were observed in natural stands from higher elevation. The individual correlation analysis based on two natural stands from different elevation in the central production region showed that the correlation among traits were quite different and depending on different elevation of stands. In high elevation stands, bark traits could be used as good morphological indicators for wood properties and diameter growth. Individuals with higher stem fullness usually exhibited less wood basic density, as well as bark with lighter color and smooth surface. At the same time, individuals with higher stem straightness and dark bark usually exhibited faster grew speed in diameter. For stands from low elevation, bark thickness was demonstrated to be a good indication on wood basic density and other traits, as decreased wood texture distortion degree and increased wood basic density were observed in individuals with higher stem straightness, lighter bark color and large DBH increment.