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把细叶桉和木麻黄各按2 500,10 000,40 000株/ha 栽植,并分别于1、2和3年末测定其树干材积。1年生的树干材积40 000株/ha 高密度林的约为2 500株/ha 常规密度林的20倍,2和3年生的约为10倍;1、2和3年生10 000株/ha 中密度林的收获量均约为常规密度林的4倍.两树种间彼此无差异,1、2和3年生的收获量几乎都相同。3年生树干树皮含量百分率随密度的增大而升高;高密度的与常规密度的相比,细叶桉为31%:21%,木麻黄为8%:4%。另外,讨论了短轮伐期的缺点。强调材性(如常规树皮含量、长纤维长度和高比重)和幼年速生结合起来进行选择,以便高密度短轮伐期实践更加成功。
Eucalyptus and Casuarina equiseti were planted at 2 500, 10 000 and 40 000 plants / ha, respectively, and their trunk dry weight was measured at the end of 1, 2 and 3 years respectively. Annual trunk volume of 40,000 trees / ha for high-density forest is about 20 times higher than that of conventional forest of 2,500 trees / ha, and about 10 times for secondary and tertiary trees; The density of forest harvesting is about 4 times that of conventional density forest, no difference between the two species, and almost the same amount of harvest in 1, 2 and 3 years. The percentage of tree bark content of 3-year-old tree increased with the increase of density; high-density eucalyptus was 31% with 21% and Casuarina equisex with 8% with 4% compared with the normal density. In addition, the shortcomings of the short rotation period are discussed. Emphasis on material properties (such as regular bark content, long fiber length, and high specific gravity) is combined with juvenile rapidity to make the selection more successful in high-density short rotation.