SEM-EDXA分析不同生长应力木材细胞壁微区木质素沉积

Microanalysis Study on Lignin Distribution of Wood with Different Growth Stress Level by SEM-EDXA

选取具不同生长应力水平的人工林尾巨桉(Eucalyptus urophylla×E.grandis)正常木为研究对象,借助场发射环境扫描电子显微镜系统,结合以溴元素做标记的X射线能谱分析技术,分析了尾巨桉细胞壁微区木质素沉积与生长应力的关系。研究结果表明,木纤维细胞壁各微区间木质素含量的大小关系与生长应力高低无关,其含量顺序为细胞角隅>复合胞间层>次生壁(S1>S2>S3);而随着生长应力增大,木纤维细胞壁各微区木质素含量均下降,木质化进程减慢。

By virtue of FE-SEM and EDXA marked by Br element,the relationship between the lignin distribution and growthstress was micro-analyzed by normal wood of plantation Eucalyptus urophylla×E.grandis with different growth stress levels.The results indicated that the lignin contents of different cell wall layers were not related to the growth stress level,and the lig-nin content（from high level to low level）in sequence was cell corner,compound middle lamellae,S1,S2and S3;The lignin con-tents in micro-morphological regions of wood fiber cell wall were decreased with the increase in growth stress and lignificationprocess was delayed.