不同间伐强度对华北落叶松人工林天然更新的影响  

Effects of Different Thinning Intensities on the Natural Regeneration of Larix principis-rupprechtii Plantations

作　　者：姜雨 白宇 吕宝磊 李丹阳 马莉薇 JIANG Yu;BAI Yu;LÜBao-lei;LI Dan-yang;MA Li-wei(School of Forestry,Hebei Agricultural University,Baoding 071000,Hebei,China)

机构地区：[1]河北农业大学林学院,河北保定071000

出　　处：《西北林学院学报》2024年第4期39-45,260,共8页Journal of Northwest Forestry University

基　　金：河北省自然科学基金项目(C2021204002);2021年度引进留学人员资助项目(C2021036)。

摘　　要：研究塞罕坝30年生华北落叶松(Larix principis-rupprechtii)人工林抚育间伐强度对天然更新空间点格局及种间关联性的影响规律,对于塞罕坝人工林空间结构调整和天然更新保护具有重要意义。以塞罕坝地区华北落叶松人工纯林为研究对象,设置高(60%~65%)、中(45%~50%)、低(35%~40%)3种间伐强度及对照固定样地各3块,每块样地面积均为900 m^(2),间伐前平均密度为2611株/hm^(2)。运用g(r)和g_(12)(r)函数,研究不同间伐强度下天然更新个体特征变化、主林层大树与天然更新格局及种间关联性变化。其中,林下乔木更新物种数在不同间伐强度之间没有显著差异,中度间伐强度的平均高度、平均基径和平均冠幅均为最大值,分别达到了52.68、5.18 cm和34.49 cm,只有平均密度在中间伐强度下为最小值,为93株/hm^(2)。主林层空间点格局以随机分布为主;天然更新空间点格局以聚集分布为主;天然更新和主林层种间关联性以不相关为主。研究结果表明,中等间伐强度(45%~50%)有利于调整塞罕坝地区华北落叶松人工纯林空间结构和保护天然更新。The objective of this study was to investigate the effects of different thinning intensities on the spatial pattern and interspecific correlation of the natural regeneration of 30-year-old Larix principis-rupprechtii plantations that is crucial for adjusting the spatial structure and conserving natural regeneration of the artificial forests in the Saihanba Forest Farm.The pure forest of L.principis-rupprechtii in Saihanba area was selected as the research object.Three kinds of thinning intensity were set up:high(60%-65%),medium(45%-50%)and low(35%-40%),and three fixed plots each with an area of 900 m^(2) were set respectively.The average tree density before thinning was 2611 trees/hm^(2).The g(r)and g12(r)functions were utilized to investigate the changes in individual characteristics of natural regeneration,the spatial pattern between dominant canopy trees and natural regeneration,and the interspecific correlation under different thinning intensities.The results indicated no significant differences in species richness among the various thinning intensities.The medium thinning intensity exhibited the highest values for average height,average diameter at breast height,and average crown width,reaching 52.68 cm,5.18 cm,and 34.49 cm,respectively.Only the average density was the lowest under the medium thinning intensity,at 93 stems/hm^(2).The spatial pattern of the dominant canopy layer was primarily random,while that of natural regeneration was predominantly aggregated.The interspecific correlation between natural regeneration and the dominant canopy layer was mainly unrelated.The resuls of this study suggests that a medium thinning intensity(45%-50%)is advantageous for adjusting the spatial structure of pure L.principis-rupprechtii plantations and conserving natural regeneration in the Saihanba Forest Farm.

关 键 词：华北落叶松 抚育间伐 天然更新 空间点格局 种间关联性 

分 类 号：S756.9[农业科学—森林经理学]