不同间伐措施对乳源木莲生长的影响

由于间伐措施不同,杉木与乳源木莲混交林中的乳源木莲生长差异显著。间伐适时,乳源木莲的胸径、树高生长量明显增加,材积速生期延长,且17年生仍处在速生期;而逾期间伐,林分密度偏大,则混交林中乳源木莲生长受抑制,速生期提早结束,生长不良。作者认为,为提高杉莲混交林的经营效果,适时间伐、密度合理至关重要。

Effects of different thinning measures on the growth of Manglietia yuyuanensis

The growth of Manglietia yuyuanensis in mixed plantations of China fir and Manglietia yuyuanensis was varied significantly by different thinning measures. It was found that 9th year after planting was the optimal time for the first thinning and timely thinning could lengthen the prime stage of Manglietia yuyuanensis growth and increased the increment of DBH, height and volume. For example, 17 year-old trees were still in fast-growing period. For first thinning at 12th year after planting, the stand density was higher than that at 9th year, the growth was inhibited and the fast growing period was shortened. The proper time for first thinning and proper stand density were important for the effective management of mixed plantations.