生长在太白山上的紫萼丁香木材的生态解剖

生长在秦岭太白山北坡的紫萼丁香(Syringa oblata var.giraldii Rehd.)的木材结构随着海拔高度的增加而变化。其年轮宽度,导管分子长度、直径;纤维管胞长度、宽度;射线高度等值逐渐增加。导管频率、射线频率、单孔率值则逐渐减少。导管、纤维管胞的壁减薄,其次生壁上的螺纹加厚由明显到不明显。

THE ECOLOGICAL WOOD ANATOMY OF THE LILAC(SYRINGA OBLATA VAR.GIRALDII REHD.)IN TAIBAI MOUNTAIN

The wood structure of Syringa oblata var.giradii Rehd.grown on the north side of Taibai Mountain varied with the increasing altitude:the width of growth ring,the length of vessel member,the vessel diameter,the length and width of fibretracheid and the ray height gradu- ally increased with the altitude;the frequency of vessel,the frequency of ray and the frequ- ency of solitary vessels decreased;the vessel and fibretracheid walls grew thinner.The spiral thickenings of the vessel wall and the fibre-tracheid wall in the lower altitude are more evi- dent and them gradually obscure.