应拉木胶质层解剖结构及化学主成分结构特征  

Anatomical Structure and Structure Characteristic of Chemical Composition of Gelatinous Layer in Tension Wood

作　　者：苌姗姗[1] 石洋 刘元[1] 胡进波[1] Chang Shanshan;Shi Yang;Liu Yuan;Hu Jinbo(College of Materials Science and Engineering, Central South University of Forestry and Technology Changsha 410004)

机构地区：[1]中南林业科技大学材料科学与工程学院,长沙410004

出　　处：《林业科学》2018年第2期153-161,共9页Scientia Silvae Sinicae

基　　金：湖南省自然科学基金项目(2017JJ1038);国家自然科学基金项目(31300481);湖南省教育厅优秀青年项目(16B281);湖南省科技计划项目(2016NK2160);湖南省林业科技计划项目(XLK201634)

摘　　要：树木为了保持树干笔直或使树枝恢复到正常位置而产生生长应力,树木中具有这种应力的部位被称之为应力木。在天然阔叶林中,树木发生倾斜、弯曲和偏冠时,树干和枝条的上方受拉伸应力,受拉部位的木质部即为应拉木。然而在人工林速生树种的垂直树干中,也大量存在应拉木,但其结构、性质与正常材差异很大,给木材加工利用带来了一系列问题。与正常木相比,应拉木纤维细胞壁结构差异很大,特别是其纤维腔壁内表面常具有特殊形态和化学组成的壁层——胶质层,该壁层具有纤维素含量高、结晶度大、木质素含量低、微纤丝角小和纳米孔隙丰富等特征。因胶质层出现与应拉木中高拉伸应力的产生直接相关,当胶质纤维集中时,木材在干燥和加工利用过程中易产生扭曲、开裂、夹锯和板面起毛等一系列问题,严重制约优质人工林的培育和木材的合理加工利用,造成了大量经济损失。因此,深入了解应拉木与正常木在结构和功能上的差异,特别是应拉木胶质层的特殊结构、化学成分与其生物学功能间的内在联系是深入探究应拉木高拉伸应力产生机制的关键所在,同时也是木材学、植物学、树木生理学和材料学等学科领域研究的交叉前沿问题,对于减少因应拉木缺陷造成的损失、提高木材品质和利用率具有重要的理论意义和实际价值。本文对应拉木胶质层解剖结构及化学主成分结构领域的主要研究现状进行归纳,尤其对胶质纤维在应拉木中的分布特征、胶质层的解剖结构、孔隙结构和化学主成分等方面的最新研究做了详细介绍,旨在剖析应拉木胶质层的结构和特性及其在应拉木形成过程中的作用,为探究应拉木高拉伸应力形成机制提供基础数据。针对我国人工林普遍存在的应力木比例高、材质不均匀等特点,当前学术界和工业界亟需解决的是主要人工�Growth stress is generated in order to keep the trunk straight,or the branches back to the normal position of trees. Trees with this stress site is called reaction wood. In natural hardwood species,tension wood is formed usually when tree is tilt,or bending and partial crown. However,in the vertical trunks of plantation fast-growing species,there exists a lot of tension wood,but its structure and properties are different from normal wood which brings a series of problems in wood processing and utilization. The fibre cell wall structure of tension wood is very different from that of normal wood,especially in the inner surface of the fiber there is a cell wall layer with special morphology and chemical component,which is called gelatinous layer. This layer has many characteristics such as high content of cellulose,large crystallinity,low lignin content,small microfibril angle and abundant nanopores. Due to the occurrence of gelatinous layer is directly correlated with high tensile stress generation of tension wood,when this layers are concentrated,wood is prone to produce a series of problems such as twisting,cracking,sawing and pilling on the board surface during wood drying and processing,which seriously restricts the cultivation on high-quality plantation and the reasonable utilization of wood,resulting in a lot of economic losses. Therefore,to deeply understand the differences in tension wood and normal wood,especially the internal relations of special structure,chemical composition and biological function of gelatinous layer is the key to explore the high tensile stress generation mechanism,as well as the frontier intersection research in wood science,botany,tree physiology and materials science. This will reduce the loss caused by tension wood defects,improving the quality and utilization of wood. This paper reviews the research on the anatomical structure and structure characteristic of chemical component of gelatinous layer in tension wood,especially the research on the distribution of gelatinous fibers in

关 键 词：应拉木 胶质层 解剖结构 孔隙结构 化学成分 

分 类 号：S718.4[农业科学—林学]