不同种源杉木木材特性的比较研究

Comparative Study on Wood Characteristics of Cunninghamia lanceolata from Different Provenances

[目的]比较不同种源杉木人工林木材特性的差异,分析不同种源杉木材性的地理分布规律,筛选材性较优的杉木种源。[方法]选择1958年营造的全国第一片杉木种源试验林,进行不同种源杉木的生长调查,取样测定不同种源杉木木材密度、管胞形态、干缩性、湿胀性、顺纹抗剪强度、顺纹抗压强度、抗弯弹性模量、抗弯强度、冲击韧性、硬度等指标,比较不同种源杉木木材材性差异,采用聚类分析和主成分分析方法,对不同种源杉木木材特性进行综合评价。[结果]结果表明,9种不同种源杉木的木材特性存在显著差异(P<0.05),木材干缩性和湿胀性有随纬度增加而增大的趋势,但其他材性指标无明显的地理变异规律。安徽休宁种源木材密度显著高于其他种源(P<0.05),管胞长宽比大小排序为:广东郁南>浙江金华>福建南平>四川彭县>四川庐山>湖北竹溪>湖南会同>安徽休宁>贵州剑河。安徽休宁种源的差异干缩最小,贵州剑河种源的体积干缩系数最小。福建南平种源木材抗弯弹性模量和抗弯强度最高,安徽休宁种源木材冲击韧性和顺纹抗剪强度最高,广东郁南种源木材顺纹抗压强度最高,四川庐山种源木材硬度最高。不同材性指标间存在显著相关性,木材密度与部分力学性质显著相关。根据不同种源杉木材性的差异,将9种种源杉木分为3类,福建南平、广东郁南、四川庐山和安徽休宁种源归为一类,四川彭县、浙江金华、湖北竹溪和湖南会同种源归为一类,贵州剑河种源归为一类。综合不同材性指标对9种种源杉木材性的综合评价排序为安徽休宁>四川庐山>福建南平>广东郁南>四川彭县>浙江金华>湖北竹溪>湖南会同>贵州剑河。[结论]地理种源在一定程度上对杉木木材材性有重要影响。

[Objective]The study aims at comparing the differences of wood characteristics of Chinese fir(Cunninghamia lanceolata)plantations from different provenances and analyzing their geographical variation regularity,so as to screen the better Chinese fir provenance.[Method]The first provenance test plantation of Chinese fir planted in 1958 was selected as the research object.Through investigating the growth of Chinese fir from different provenances,the intermediate trees were determined.The wood density,tracheid morphology,dry shrinkage,wet swelling,shear strength parallel to grain,compression strength parallel to grain,bending modulus of elasticity,bending capacity,impact property and hardness were determined and compared.The wood properties were evaluated by cluster analysis and principal component analysis.[Result]Significant differences were found in wood characteristics among nine provenances of Chinese fir(P<0.05).The dry shrinkage and wet swelling of wood increased with latitude,but there was no significant geographical variation regularity in other wood characteristics.The wood density of Anhui Xiuning provenance was significantly higher than that of other provenances(P<0.05).The rank order of the tracheid length-width ratio is as follows:Guangdong Yu'nan provenance>Zhejiang Jinhua provenance>Fujian Nanping provenance>Sichuan Pengxian provenance>Sichuan Lushan provenance>Hubei Zhuxi provenance>Hunan Huitong provenance>Anhui Xiuning provenance>Guizhou Jianhe provenance.The ratio of tangential to radial shrinkage of Anhui Xiuning provenance and volume shrinkage coefficients of Guizhou Jianhe provenance were the lowest.The bending modulus of elasticity and bending capacity of Fujian Nanping provenance were the highest.The impact property and shear strength parallel to grain of Anhui Xiuning provenance were the highest.The compression strength parallel to the grain of Guangdong Yu'nan provenance was the highest,while the hardness of wood from Sichuan Lushan provenance was higher than that of other provenances.A significant correlation between wood characteristics index and wood density was significantly correlated with some wood characteristics index.According to the difference of wood properties of different provenances,nine provenances of Chinese fir were clustered into three categories:category I included Fujian Nanping provenance,Guangdong Yu'nan provenance,Sichuan Lushan provenance and Anhui Xiuning provenance,category II included Sichuan Pengxian provenance,Zhejiang Jinhua provenance,Hubei Zhuxi provenance and Hunan Huitong provenance,category III included the Guizhou Jianhe provenance.Using comprehensive analysis,the rank order for wood properties of the nine provenances is as follows:Anhui Xiuning provenance>Sichuan Lushan provenance>Fujian Nanping provenance>Guangdong Yu'nan provenance>Sichuan Pengxian provenance>Zhejiang Jinhua provenance>Hubei Zhuxi>Hunan Huitong provenance>Guizhou Jianhe provenance.[Conclusion]Geographical provenance has an essential influence on wood properties of Chinese fir to a certain extent.