Physical and mechanical properties and radial variation of different poplar clones grown in Songnen Plain,Northern China
[Objective]The study compared the physical and mechanical properties of woods and radial variation among different clones of poplar trees.The aim was to provide a theoretical basis for the selection and efficient utilization of excellent germplasm resources and wood in poplar breeding.[Method]Four clones of poplar trees,namely,HQ(Populus euramericana'N3016'×P.ussuriensis),QS(Poplars cathayana×P.deltodides),XH(Populus simonii×Populus nigra),YZ(Populus alba×P.berolinensis),collected from Cuo Hai Forest Farm in Heilongjiang province,were selected as the research subjects.The physical and mechanical properties of the woods were determined according to national standards,and the differences in wood properties and radial variation patterns between different strains were analyzed.The membership function method was used to comprehensively evaluate the wood properties.[Result]The measured values of the basic density,air-dry density,oven-dry density,air-dry shrinkage of volume,air-dry shrinkage ratio difference,absolute-dry shrinkage of volume,absolute-dry shrinkage ratio difference,swelling rate of volume,swelling rate ratio difference,modulus of elasticity,bending strength,and compression strength parallel to grain of the four poplar clones ranged between 0.29-0.38 g·cm-3,0.36-0.47 g·cm-3,0.34-0.43 g·cm-3,7.31%-8.56%,1.50-3.16,9.96%-11.04%,1.45-2.82,14.73%-16.55%,1.40-1.82,4.7-7.60 GPa,56.09-90.78 MPa,40.75-57.44 MPa,respectively.The dimensional stability of the wood in the radial direction was superior to that in the tangential direction.Among the different strains,the YZ showed the best performance in terms of density,shrinkage ratio difference,swelling rate ratio difference,and mechanical properties,while the air-dry shrinkage of volume and swelling rate of the HQ were the smallest.In terms of radial variation,the variation pattern of wood properties from pith to bark differed among the different strains,showing as follows:the basic density of HQ and QS initially decreased and then increased,while that of XH and YZ increased continuously.The swelling rate ratio difference of HQ initially decreased and then increased,while that of XH and YZ increased continuously,and the swelling rate ratio difference of YZ decreased continuously.The volume swelling rate and mechanical properties of the four poplar clones gradually increased.The comprehensive performance of the wood near the bark was superior to that near the pith.[Conclusion]The fuzzy membership function analysis concludes that the YZ has the best comprehensive evaluation of wood properties among the four clones and is the most suitable for directed cultivation as an excellent variety for industrial use in poplar wood.
万方数据
维普
