| Based on the GB1927—1942—91 standard of 《Experimentation Methods of Wood' s physical mechanical property》 , this paper studied the methods of wood's physical mechanical property for the plantation of the Eucalyptus grandis in Sichuan which introduced from Australia, and the study of physical property includes woods density, hydrous rate , shrinkage rate, wet swelling, absorbs water rate. Researches of mechanical property include compressive strength parallel to grain, bending strength, modelus of elasticity in bending strength, shearing strength parallel to grain, felling shake, toughness and hardness. All the 9 samples come from Fu-shun County, Dan-ling County, Jia-jiang County, and Qian-wei County, which represent four different cultivation measures respectively. This paper studied the affection of different silvicultural measures to the Eucalyptus grandis wood property, and discussed the management measures to improve the wood property of the Eucalyptus grandis. The main research results are as follows:1. The plantation of the Eucalyptus grandis average wood air-dried denisty is between 0. 437 and 0. 580g/cm~3, and among these woods, the woods (11.8 years) come from Fu-shun County with thinning measures with the air-dried denisty of 0.580g/cm~3, belong to medium range, indicate that the older the tree with thinning measures is, the bigger the wood' s air-dried denisty is. The woods come from Qian-wei County with the air-dried denisty of 0.498g/cm~3, belong to lower range; The woods come from Dan-ling County only with apply fertilizer to the subsoil measures and woods comes Jia-jiang County with apply fertilizer measures have different air-dried denisty, respectively 0.541g/cm~3 and 0.437g/cm~3, which shows that fertilization may decrease the wood' s air-dried denisty.2. Wood' s basic denisty is between 0. 394 and 0. 528g/cm~3, single apply fertilization measures can't increase the wood's basic denisty of the Eucalyptus grandis. The plantation Eucalyptus grandis (6 years) in Sichuan has nearly the same wood basic denisty compared with the plantation of Eucalyptus grandis abroad, which indicate that it has a better wood property, and will also get a better development.3. The woods come from Fu-shun County (11.8 years) with thinning measures have higher property in those indexes such as compressive strength parallel to grain, bending strength, modelus of elasticity in bending strength, shearing strength parallel to grain, felling shake, toughness and hardness, and the relative difference is between 3. 55~ 31.63%. Proper thinning won't decrease the physical mechanical property of the wood, on the contrary, it will fasten the growth of trees. So, when we are making our silvicultural plans, for construction, furniture and veneer use, we can adopt thinning measures to fasten the growth of trees to meet the requires of utilization.4. The woods come from Jia-jiang County with apply fertilizer measures have lower property than those woods come from Qian-wei County without apply fertilizer measures in those indexes such as compressive strength parallel to grain, bending strength, modelus of elasticity in bending strength, shearing strength parallel to grain, toughness and hardness, but have higher property in felling shake. Shrinkage rate of the wood volume is lower than those in Qian-wei, which can improve the stability of wood dimension. This means that apply fertilizer may decrease some physical mechanical property of wood, but at the same time it can improve the other wood property indexes. Fertilization measures can fasten the growth of trees, improve the height, chest high diameter and volume, and the wood quality can also meet the requires such as pulpwood and furniture wood production.5. Comparing the woods come from Dan-ling County (7. 7years) with apply fertilizer to the subsoil measures with the woods come from Qian-wei County (5. 5years) without apply fertilizer measures, the former's basic denisty increased by 13. 58%. Apply fertilizer to the subsoil could reduce the shrinkage of woods and improve those indexes such as the bending strength, shearing strength parallel to grain of radial section, felling shake , toughness and hardness, which indicate that the older tree with apply fertilizer to the subsoil measures have higher physical mechanical property in many indexes.6. Based on the analysis of how different cultivation measures influence the property variation rules of woods, this paper constructed an optimal silvicultural model of the plantation of the Eucalyptus grandis that used for industry fiber and big dimension woods purpose, which can also guide the purposeful cultivation and utilization in some extent.7. Management measures which can improve the property of the plantation of the Eucalyptus grandis includes: appropriate site conditions, fitting planting density, proper thinning and circulation period, fertilization and pruning.
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