农田防护林木材材质物理特性研究

对早柳和小青杨的年轮宽度、年轮密度、木材纤维长度和干缩率及其径向变异进行了研究．结果表明，木材物理特性受年轮年龄的影响显著，而纤维长度不受年轮宽度影响．综合材质物理特性的径向变异规律，可将旱柳和小青杨整个生长期划分为４个时期：幼林期、速生期、成熟期和更新期，确定了各生长期的年龄值．

Physical properties of wood quality of farm shelterbelts

Studies on the width and density of ring and the length, shrinkage rate and their radial variations of wood fiber of Salix matsudana and Populus pseudo-simonii show that the physical properties of wood are significantly affected by its ring age,and the fiber length of wood is not influenced by ring width.Through synthesizing the radial variation patterns of wood properties,it is suggested that the whole growth period of these two kinds of tree species can be divided into young growth, fast-growing,mature and regeneration stages.The age value of each stage is defined.