Studies On Wood Properties And Variation Of Plantation Poplar

In the study,6 trees of plantation poplar 1-69 (Populus deltoides CV. 1-69/55),growing in the forest station in the suburb of Tianchang city Anhui Province were selected as the materials. The research fields covered the anatomical features,the tissue proportion,the microfibrillar angle,the ring width,the basic density,the fiber saturation point,the shrinkage,the wood color properties,the mechanical properties and the influence in wood properties of the fertilization. The results are as follows:1. Variation patterns of the main anatomical features and physicalproperties of plantation poplar 1-69a) The radial variance:From pith outward,the fiber length,the fiber width,the ratio of fiber length to fiber width,the proportion of vessel,the tangential shrinkage rate from wet to oven-dry of plantation poplar 1-69 wood all increase by year,reach maximum at some year and then,decrease gradually or level off;the microfibrillar angle,the proportion of fiber and ray,the fiber saturation point,the radial shrinkage rate from wet to oven-dry and the wood color properties of plantation poplar 1-69 wood all decrease gradually,reach minimum at some year and then fluctuate or level off;while the cell wall width,the ratio of cell wall width to lumen width increase or decrease insignificant,mostly fluctuate above or below a axis;the wood density and ring width of plantation poplar 1-69 wood mostly increase a little.b)The axial variance:From the base upward,the fiber length,the microfibrillar angle,the basic density of plantation poplar 1-69 all decrease to height 1.3m,increase from the height 1.3m to 4m,then decrease gradually or level off;the fiber width,the cell wall width,the ratio of cell wall width to lumen width of plantationpoplar 1-69 increase gradually,reach maximum at certain height,then decrease slightly;the tissue proportion level off or fluctuate.c) The radial variance of wood properties all above is larger than that of the axial variance. That is to say,the influence of "cambium age" on wood properties is larger than that of "tree height" on the wood properties.d) The fiber length (y) of plantation poplar 1-69 could be predicted at the beginning by ring width (x),and the effect of the predictive model Y=aX2+bX+c was superior to the model y=A+BX,with the correlation coefficient were all above 0.80.e) The color parameters of plantation poplar 1-69 distribute in the CIE color system and Munsell color system. In the CIE color system,the lightness L ranged from 56.07 to 89.73;the hue value a ranged from 1.90 to!4.22 and the hue value b ranged from 5.16 to 27.83,while in the Munsell color system the lightness V ranged from 4.46 to 7.83,the hue value H mostly distributed around 8Y. A larger or smaller correlation was in the color parameters of plantation poplar 1-69 above,which stand for the particular characteristics in wood color.2. The main mechanical properties of plantation poplar 1-69The mean value of modulus of rapture is 75.44 Mpa,the mean value of modulus of elasticity is 6657.9 Mpa,the compressive strength parallel to the grain is 42.16 Mpa. The mechanical strength properties are the lower levels in the terms of the wood physic-mechanical classifying criteria,while the properties of 1-69 is relatively good,in the Populus wood. Regressive analysis shows that each mechanical properties positively related to density and the mechanical properties positively related to each other.3. The comparison between wood properties of plantation poplar 1-69 in different fertilizationa) anatomical changes:Compared to unfertilized plantation poplar 1-69 the fertilized have smaller fiber length,fiber width,lumen width,and the larger cell wall width,the ratio of fiber length to fiber width,the ratio of cell wall width to lumen width,microfibrillar angle,ring width. No difference were foundsignificant among the properties above.b) physical changes: It was significant of the influence of the fertilization in plantation poplar. The value of wood density, shrinkage properties,color par...