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在全国杉木中心产区 ,选择不同栽植代数 ( 1、2、3代 )、不同发育阶段 ( 5、1 0、1 5、2 0年 )、不同立地 ( 1 4、1 6、1 8地位指数 )的杉木人工林 ,进行不同栽植代数杉木人工林生长发育特点的比较研究 ,结果表明 :连栽导致了杉木生长的明显衰退 ,2、3代杉木胸径分别比 1代杉木下降 7 2 9%～ 1 1 61 %和 1 5 63 %～ 2 1 4 7% ,树高分别下降 7 89%～ 1 1 76%和 1 7 76%～ 2 2 3 5% ,蓄积量分别下降 2 1 0 2 %～ 2 4 61 %和 3 8 70 %～ 4 4 1 8% ,而且随栽植代数的增加 ,杉木胸径、树高生长速生期开始时间推迟 ,速生期缩短 ,林木分化日趋明显 ,中级木比例减少 ,大、小级木比例增加。
In the Cunninghamia lanceolata producing areas, different planting algebra (1, 2 and 3 generations), different developmental stages (5,1 0,1 5,20 years), different site (1 4,1 6,1 8 position index ) Of Chinese fir plantations, the growth characteristics of different plantation alpine Chinese fir plantations were compared. The results showed that: Continuous planting led to the obvious decline of Chinese fir growth. The DBH of 2nd and 3rd generation Chinese fir decreased by 7 2 9% 1161% and 1563% ~ 2147% respectively, the tree height decreased by 7 89% ~ 1176% and 17 76% ~ 2235% respectively, and the stock volume decreased by 21.02% ~ With the increase of planting algebra, the start time of DBH and height growth and deceleration of Chinese fir was postponed, the shortening of fast growing period, the differentiation of tree species became obvious, the proportion of intermediate wood decreased, , Small proportion of wood increased.