论文部分内容阅读
通过对南平溪后２９年实生杉木不同连栽代数生长过程的分析，结果表明：１代和２代杉木在１０年生前树高、胸径和材积的生长量相近，此后，２代的生长迅速下降（早衰），２９年生的平均单株材积比１代的下降４１４６％。３代杉木树高、胸径和材积生长一开始就比２代的差，但未出现大幅度的衰退现象，２９年生的单株材积比２代的下降１７７０％。杉木栽植代数越少，生长高峰出现时间越早，峰值越大，速生期持续时间亦越长。
The results showed that the growth of tree height, diameter at breast height and volume at 1 year and 2 generations of Chinese fir was similar after 10 years of age, and then the growth of the 2nd generation decreased rapidly (Premature senescence). The average single plant volume at 29 years old was 41.46% lower than that of the first generation. The height, DBH and volume growth of the 3rd generation of Chinese fir were worse than those of the 2nd generation at the beginning, but there was no significant decline. The annual volume of 29-year-old plant was 17.7% lower than that of the 2nd generation. The fewer fir planting algebra, the earlier the peak of growth appears, the larger the peak is, and the longer the duration of fast-growing period is.