我国南方湿地松木材物理力学性质变异初探

我国南方五省区湿地松木材的密度、晚材率和各项力学强度,随纬度的增加,呈递减状态。纬度与气干容重之间的直线回归方程为:G=1.28—0.027L,相关系数r=0.984.产生此现象的主要原因是,木材的管胞宽度和厚度随着纬度的增加逐渐变窄、变薄。产地的年平均气温和年降水量对湿地松树木的年轮宽度和晚材带宽度影响较大;年轮和晚材带的平均宽度随产地自北向南依次增加,随着山地海拔的升高而减小。

THE VARIATION IN PHYSICAL AND MECHANICAL PROPERTIES OF SLASH PINE IN SEVERAL SOUTHERN PROVINCES OF CHINA

The higher the latitude, the smaller become the specific gravity, the latewood percentage and the mechanical strength of slash pine which grows in four provinces and an autonomous region of the southern China.The relation between latitude (L) and specific gravity (G) of Slash pine, based in air dring condition,can be expressed as the following re-gressional equation: G= 1.28 -0.027L(r = 0.984) .The reason for this is that the wood-tracheid width generally gets larger and tracheid wall thickness becomes thinner when the regional latitude gets higher.In addition, the annual average temperature and the rain fall have the significant effect on the width of tree ring and latewood zone.In general, the average lat-ewood zong width increases with the forest land moving from north to south. Meanwhile, with hight above sea level going up, the width of tree ring and latewood zone of Slash pine will become narrower.