内蒙古大兴安岭林区兴安落叶松人工林密度控制图研究  

Density Management Diagrams for Larix gmelinii Plantations in Daxing’an Mountains

作　　者：徐旭平 吕延杰 王建军 XU Xuping;LYU Yanjie;WANG Jianjun(East China Academy of Inventory and Planning of National Forestry and Grassland Administration,Hangzhou 310019,China;Research Institute of Forestry Policy and Information,Chinese Academy of Forestry,Beijing 100091,China)

机构地区：[1]国家林业和草原局华东调查规划院,杭州310019 [2]中国林业科学研究院林业科技信息研究所,北京100091

出　　处：《自然保护地》2023年第4期79-88,共10页Natural Protected Areas

摘　　要：【目的】构建内蒙古大兴安岭地区兴安落叶松人工林收获预估密度控制图,为科学经营,合理调控林分密度、促进林木生长、提升蓄积收获量提供参考。【方法】以内蒙古大兴安岭林区的兴安落叶松人工林为研究对象,利用四期一类清查复测样地的142块样地数据,应用Reineke自然稀疏方程拟合生长曲线,构建林分密度控制图,并模拟无经营措施、合理间伐、重度疏伐3种模式下林分生长状态及收获量。【结果】Reineke自然稀疏方程拟合效果良好,其决定系数R2为0.911,均方根误差RMSE为0.008;优势高模型、蓄积模型2个辅助方程的拟合效果良好,其决定系数R2均在0.9以上;应用最优生长密度上限与下限、林分郁闭线以及2个辅助方程绘制了密度控制图。模拟结果表明,采用合理间伐、两次疏伐及达到目标胸径时,年平均收获量明显高于其他两种林分。同时,合理间伐林分达到目标胸径时的年龄、优势高均低于无经营措施林分,总收获量明显高于其他两种林分。【结论】大兴安岭林区兴安落叶松人工林密度控制图通过林分因子之间的关系直观展现了林分生长状态和抚育经营效果,并发现林分进入自然稀疏阶段后将密度控制在349~757株/hm2,能够提高达到目标胸径时林分蓄积总收获量。【Objective】A Density Management Diagram(DMD),which includes growth and yield estimation functions and is designed to facilitate reasonable silvicultural measures,has been developed for Larix gmelinii plantations in the Daxing’an Mountains.【Method】The focus of this research was on the growth of Larix gmelinii plantations in Inner Mongolia Autonomous Region.Based on four times Chinese National Forest Inventory,142 sample plots were collected.Reineke self-thinning equation was used to fit the growth curve and develop DMD.Based on DMD,the stand growth dynamic and yield was simulated under three different silvicultural measures:no management,reasonable thinning,and heavy thinning.【Result】The Reineke self-thinning equation showed a good fitting effect with R2 of 0.911 and RMSE of 0.008.The dominant height,and volume models fitted as auxiliary equations,with R2 values above 0.9.The upper limit,lower limit,closed canopy lines,and two auxiliary equations were jointly drawn the DMD.Simulation results show that achieving the target stand average diameter at breast height(QMD)after two thinning resulted in a stand average yield of 19.25 m3/hm2 in the reasonably thinned stand,which was higher compared to the no-management stand,and the heavily thinned stand.The age and dominant height of the reasonably thinned stand in the target QMD were lower than that of the no-management stand,and the stand yield was significantly higher than the other two stands.【Conclusion】The DMDs of Larix gmelinii plantations in Daxing’an Mountains can directly show the stand growth and the effectiveness of management practices through the relationship among stand parameters,and after self-thinning,stands with a density between 349 and 757 trees/hm2 could improve the yield of the stand under the target diameter.

关 键 词：密度控制图 兴安落叶松 自然稀疏 林分经营模拟 

分 类 号：S753[农业科学—森林经理学]