武夷科学

通过分析不同间伐作业方式对杉木中龄林林分生长的影响，探索当前杉木人工林实际生产实践中，适宜杉木中龄林的科学抚育措施。本试验选择12年生杉木人工林为研究对象，设置了砍大留小(处理1)、砍两头留中间(处理2)、砍小留大(处理3)3种抚育间伐作业方式，以未间伐为对照处理，测定分析不同处理条件下杉木胸径、树高、蓄积量、碳储量和林分整齐度等生长指标。结果表明，间伐5 a后，在处理3条件下，杉木林分平均胸径最大，为18.69 cm,显著大于对照组和处理1(P<0.05),但与处理2的差异未达显著水平(P>0.05);在树高生长方面，处理3的平均树高最高，为16.49 m,与处理2的差异未达显著水平(P>0.05),但显著高于处理1(P<0.05);在林分蓄积量和碳储量方面，处理1显著低于处理2和处理3(P<0.05),处理2和处理3之间无显著差异；在林分整齐度方面，处理2在胸径整齐度和树高整齐度均表现最优。综上考虑，认为处理2的抚育间伐作业方式在森林经营实践过程中对林业基层生产具有指导意义。

By analyzing the effects of different thinning methods on the growth of a middle-aged Cunninghamia lanceolata stands, this study aims to explore the tending measures suitable for middle-aged C. lanceolata plantations in production practice. In this study, a 12-year-old C. lanceolata plantation was selected and underwent thinning in three modes: cutting the big and keeping the small(Treatment 1), cutting the big and the small and keeping the middle(Treatment 2), and cutting the small and keeping the big(Treatment 3), with non-thinning as the control. The growth indexes such as diameter at breast height(DBH), plant height, stand volume, carbon storage, and stand uniformity of C. lanceolata under different treatment conditions were measured and analyzed. The results showed that 5 years after thinning, Treatment 3 had the largest average DBH(18.69 cm), which was larger than that in the control group and Treatment 1(P<0.05) but had no significant difference from that in Treatment 2(P>0.05). The average plant height in Treatment 3 was the highest, reaching 16.49 m, which was not significantly different from that in Treatment 2(P>0.05) but higher than that in Treatment 1(P<0.05). The stand volume and carbon storage were lower in Treatment 1 than in Treatment 2 and Treatment 3(P<0.05), while neither of them showed significant difference between Treatment 2 and Treatment 3. Treatment 2 showed the best DBH uniformity and plant height uniformity. In summary, it is considered that the thinning mode of Treatment 2 has guiding significance for forest management practice.