北京林业大学学报2025，Vol.47Issue(4)：82-91,10.DOI:10.12171/j.1000-1522.20240208
密度调控对中龄米老排人工林材种结构和经济效益的影响
Effects of density regulation on timber assortment structure and economic benefits of middle-aged Mytilaria laosensis plantations
摘要
Abstract
[Objective]This paper analyzes the influence of density regulation on timber assortment structure and economic benefits of middle-aged Mytilaria laosensis plantations,so as to provide a scientific basis for management decisions.[Method]Two mature M.laosensis plantations in the southern subtropical region of Guangxi,southern China,including Shaoping experimental forest,which had undergone density regulation strategy mode Ⅰ(one thinning,resulting in a stem density of about 1200 plants per hectare),and the Qingshan experimental forest,which had undergone density regulation strategy mode Ⅱ(three thinnings,resulting in a post-thinning stand density of 520 plants per hectare),were selected as research subjects.In each stand,14 trees of different diameter classes were felled for stem analysis.The central sectional area formula was used to calculate the yield of each timber assortment,and the replacement cost method was employed to analyze economic benefits of different stands.[Result](1)Significant differences were observed in the non-cumulative yields of small-and medium-diameter timber between mode Ⅰ and mode Ⅱ(P＜0.05).(2)From the 25th year,the cumulative yield of small-diameter timber in mode Ⅱ was lower than in mode Ⅰ.From the 21st year,the cumulative yields of medium-and large-medium-diameter timber in modeⅡ were higher than in mode Ⅰ,although these differences were not statistically significant(P＞0.05).(3)The cumulative yield patterns of different timber assortments in mode Ⅰ and mode Ⅱ stands exhibited similar trends.Specifically,the cumulative yield of small-diameter timber increased with age,then slightly decreased,and finally tend to stabilize.The cumulative yield of medium-diameter timber increased with age,then stabilized.The cumulative yields of large-and large-medium-diameter timber increased with age.(4)For the production of small and medium-diameter wood,the optimal rotation period for mode Ⅰ was 17-19 years,and for mode Ⅱ,it was 17-21 years.The economic benefits between the two modes were not significantly different.However,when the primary objective was the production of large-medium-diameter wood,from the 23rd year onwards,the dynamic economic benefits of mode Ⅱ were significantly higher than those of mode Ⅰ(P＜0.05).The rotation period for mode Ⅱ should ≥ 26 years.[Conclusion]The density regulation measures of mode Ⅰ and mode Ⅱ do not significantly affect the cumulative yield and static economic benefits of different timber types in M.laosensis plantations.However,their impact on dynamic economic benefits is significant.The optimal management strategy for maximizing dynamic economic benefits in M.laosensis plantations for both mode Ⅰ and mode Ⅱ is to produce small and medium-sized timber.There is no significant difference in economic benefits between the two modes under this strategy.When the management goal shifts to producing large and medium-sized timber,the dynamic economic benefits of both modes decrease significantly with the increase in stand age.The mode Ⅰ stands will incur losses,while mode Ⅱ can still maintain a good level of profitability.关键词
米老排/密度调控/树干解析/材种结构/经济效益Key words
Mytilaria laosensis/density regulation/stem analysis/timber assortment structure/economic benefit分类
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唐继新,陈东成,潘启龙,刘衡,蒋志林..密度调控对中龄米老排人工林材种结构和经济效益的影响[J].北京林业大学学报,2025,47(4):82-91,10.基金项目
中国林业科学研究院热带林业实验中心科学基金项目(RL-2020-02),国家重点研发计划子课题(2023YFD2200901-01). （RL-2020-02）
