以1～5年生LH1无性系桉树人工林为研究对象,运用Normal分布、Weibull分布、Gam-ma分布、对数正态分布和Logistic分布对直径(树高)分布进行拟合;运用角尺度、混交度和大小比数分析林分空间结构并给出调整策略.结果表明:1)对不同林龄的按树人工林,Normal分布函数拟合直径分布总体效果较好,Logistic分布函数拟合树高分布总体效果较好;2)1～5年生按树人工林角尺度均值＜0.475,林分呈现均匀分布,林木胸径分化不严重,林分接近中庸状态;1～4年生时林分呈现零度混交,5年生时少数结构单元出现弱度混交;3)在桉树人工林的短周期经营模式中,应在第4年对林分中大小比数取值0和0.25的优势和亚优势单株进行择伐;在以培育大径材为目标的中、长期经营模式中,应在第3年对角尺度取值0、0.25且同时大小比数为0.75或1的劣势或绝对劣势单株进行疏伐,同时伐除不健康林木.%Taking 1-to 5-year-old Eucalyptus plantations (LH1 clone) as research objectives,the structural characteristics of the stands were analyzed.The distribution of diameter (or tree height) was fitted with Normal,Weibull,Gamma,Log normal and Logistic distribution functions.The spatial structures of the stand were analyzed by using uniform angle index,mingling degree and neighborhood comparison,and the adjustment strategy was given.The results showed that 1) for all the stands with different ages,the overall fitting results of diameter distribution with Normal distribution function and tree height distribution with Logistic distribution function were satisfactory.2) For 1-to 5-year-old stands,the mean value of uniform angle index was less than 0.475,and the distribution was even.The mean value of neighborhood comparison was close to 0.5,which meant that the forest DBH differentiation was not serious,and the state of forest stand was close to the mean distribution.Weak mixing was observed in a few structural units for 5-years-old stands,and zero degree mixing for 1-to 4-year-old stands.3) In the short-term management mode,the stands with uniform angle index of 0 or 0.25 should be selectively cut in the fourth year.In the medium and long-term management mode for harvesting big-diameter wood,the stands with uniform angle index of 0 or 0.25 and neighborhood comparison value of 0.75 or 1 at the same time,should be thinned in the third year.Meanwhile,unhealthy trees should be cut off.
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