Study On Relationships Between Wood Properties And Forestry Factors For Hard Wood From Plantation In Middle Subtropic In Fujian Province

Natural environment and culture measure are important factors which affect wood properties. It is necessary to study the law that forestry factors (including natural environment and culture measure) affect wood properties of each tree species. This paper attempts to do some research on relationships between wood properties and main forestry factors for hard wood tree species such as Schima superba, Choerospondias axillaris and Alniphyllum fortunei in middle subtropic in Fujian province. (1) Effects laws of forest stand ages on density, size stability ,mechanical strength ,chemical composition, thermal conductivity and their dispersion of hardwood from plantation in middle subtropic in Fujian province were analyzed and studied. The results showed that prolonging rotation appropriate could improve wood quality. (2) By analogism , the formula of wood thermal conductivity across the grain was derived for hardwood from plantation in middle subtropic in Fujian province. With the formula derived, the theoretical values of thermal conductivity for hardwood from plantation in middle subtropic in Fujian province were calculated and comparison was also made to the experimental values under the same conditions. The results showed that it was satisfactory for the theoretical values of thermal conductivity to be identical to their experimental values. (3) Effects laws of sites on density, size stability ,mechanical strength ,chemical composition, fiber morphology, tissue proportion , microfibrillar angle and their dispersion of hardwood from plantation in middle subtropic in Fujian province were analyzed and studied. The results showed that fertile site had active effect on wood quality for Choerospondias axillaries but positive effect on Schima superba and Alniphyllum fortunei. (4) Effects laws of companion tree species on density, size stability ,mechanical strength ,chemical composition, fiber morphology, tissue proportion , microfibrillar angle and their dispersion of hardwood from plantation in middle subtropic in Fujian province were analyzed and studied. The results showed that Pinus massonianna had active effect on wood quality for Schima superba and Alniphyllum fortunei as Cunninghamia lanceolata for Choerospondias axillaries. (5) Effects of sites and companion tree species on radial variation modes of fiber morphology, basic density, microfibrillar angle of hardwood from plantation in middle subtropic in Fujian province were analyzed and studied. The results showed that the radial variation modes of fiber length for Schima superba ,Choerospondias axillaries and Alniphyllum fortunei belonged to Panshinâ… neither different sites nor different companion tree species while that of basic density for Schima superba and Alniphyllum fortunei belonged to Panshinâ‘ but Panshinâ‘¡for Choerospondias axillaries. For 3 sorts of hardwood with different construction from plantation ,MFA decreased with growth ring ages and tended to stabile at certain age. (6)Difference between variances of wood properties for 3 sorts of hardwood with different construction from plantation either with different forest stand ages or growing in different sites or growing with different companion tree species were analyzed. The results showed that variances of wood properties for Schima superba was similar to that for Alniphyllum fortunei but quite different from Choerospondias axillaries . (7)By means of modern statistical analysis, the relationships between wood properties and growth character as well as the relationships between many wood properties indexes each other were analyzed and studied. (8) By means of fast cluster in sequence, bounds between juvenile wood and mature wood were divided based on radial variation laws of basic density, fiber length ,the ratio of fiber length to fiber width, microfibrillar angle of hardwood from plantation in middle subtropic in Fujian province. The result showed that Juvenile periods were divided to be different according to different wood properties indexes for either Schima superba or Choerospondias axillaris or Alniphyllum fortunei wood from plantation. By means of statistical regression, depending on the of growth ring ages, modeling equations of basic density, fiber length , fiber width ,the ratio of fiber length to fiber width, microfibrillar angle for hardwood from plantation in middle subtropic in Fujian province were built. The result showed that the cubic curve equations were fit best among all modeling equations. (9) By means of ESEM , the super-micro-structure of juvenile wood and mature wood were observed and analyzed for Schima superba, Choerospondias axillaris and Alniphyllum fortunei in middle subtropic in Fujian province.