机构地区: 湖北省宜昌市林业科学研究所宜昌443111
出 处: 《华中农业大学学报》 2007年第4期552-556,共5页
摘 要: 对湖北省宜昌市大老岭林场的5种密度15 a生日本落叶松试验林观测数据进行分析,研究了密度对历年生长量的影响,并对纸浆材轮伐期内不同密度的经济效益进行评价。结果表明:平均胸径、树高、单木材积和冠幅均表现出随初植密度减小而增大的趋势,单位面积蓄积量和枝下高则表现出随初植密度增大而增加的趋势,净现值(NPV)、效益成本比(BCR)和内部收益率(IRR)也表现出随初植密度的增大而增加的规律性;初植密度除了对15 a生日本落叶松单位面积蓄积量有极显著影响外,对其它生长量的影响均不显著。在北亚热带高山区营建短周期纸浆用材林应适当密植,初植密度可以达到每公顷4 050株或3 333株,15 a生时蓄积量最高,收益最大。 Based on the experimental forest of 5 kinds density set up during Eighth Five-year-plan period, the influence of initial density on Larix kaempferi growth and economic performance was studied. The results showed that mean DBH,height, tree volume and crown width decreased with initial density and standing stock and under branch height increased with initial density. So did NPV, BCR and IRR. The initial density had no significant effect on the growth of Larix kaempferi, except 15-year-old standing stock. The suggested initial density for short rotation pulpwood plantation of Larix kaempferi in northern sub-tropical alpine area was 4 050 trees/hm^2 or 3 333 trees/hm^2.