不同采伐强度对桉树生长和冠层结构的影响  

Effects of Different Cutting Intensities on the Growth and Canopy Structure of Eucalyptus

作　　者：黄勇 胡众恒 杜旭 李万年 杨梅[2] 莫雅芳 HUANG Yong;HU Zhong-heng;DU Xu;LI Wan-nian;YANG Mei;MO Ya-fang(State-owned Gaofeng Forest Farm of Guangxi,Nanning,Guangxi 530005;Key Laboratory for Cultivation and Utilization of Subtropical Forest Plantation,College of Forestry,Guangxi University,Nanning,Guangxi 530004)

机构地区：[1]广西壮族自治区国有高峰林场,广西南宁530005 [2]广西大学林学院广西森林生态与保育重点实验室,广西高校亚热带人工林培育与利用重点实验室,广西南宁530004

出　　处：《陕西林业科技》2024年第6期7-12,共6页Shaanxi Forest Science and Technology

基　　金：国家自然科学基金(32371856).

摘　　要：通过对比分析不同采伐强度下的桉树生长参数,如树高、胸径、单株材积、叶面积指数、平均叶倾角以及冠层开阔度等,揭示了采伐强度对桉树生长及其冠层结构的影响,为桉树人工林的抚育采伐和可持续经营提供了参考和实践指导。结果表明:(1)随着采伐强度的逐步增加,观察到桉树的叶面积指数呈现出一定的下降趋势,其平均叶倾角也有所减小,而相对应的林分冠层开阔度则明显增加;(2)在高强度采伐(HT处理)条件下,桉树的平均胸径和单株材积达到了最大值,差异显著高于未进行采伐的对照组(CK);(3)采伐强度与胸径呈显著(P<0.05)正相关,与冠层开阔度呈极显著(P<0.01)正相关,与叶面积指数和平均叶倾角呈负相关。综上所述,采伐强度对桉树人工林冠层结构和林分生长产生了积极影响,采伐强度适度增加,有利于林地冠层开阔度增加,改善了林内光照条件,促进了桉树个体胸径的生长和单株材积的积累。本研究可为桉树大径木定向培育及其可持续管理提供科学依据。This study revealed the specific effects of harvesting intensity on the growth and canopy structure of eucalyptus trees by conducting a comparative analysis of key growth parameters under different harvesting intensities,including stand height,diameter at breast height(DBH),individual tree volume,leaf area index(LAI),mean leaf angle(MLA),and canopy openness.The findings provided important scientific reference and practical guidance for thinning strategies and sustainable management of eucalyptus plantations.The specific research results are as follows:(1)As harvesting intensity gradually increases,a certain decreasing trend was observed in the LAI of eucalyptus trees,with a reduction in MLA and a corresponding significant increase in canopy openness;(2)Under high-intensity harvesting(HT treatment)conditions,the average DBH and individual tree volume of eucalyptus trees reached their maximum values,with significantly higher differences compared to the control group(CK)without harvesting;(3)Harvesting intensity showed a significant positive correlation(P<0.05)with DBH and an extremely significant positive correlation(P<0.01)with canopy openness,while it exhibited a negative correlation with LAI and MLA.In summary,harvesting intensity has a positive impact on the canopy structure and stand growth of eucalyptus plantations.A moderate increase in harvesting intensity favors an increase in canopy openness,improves light conditions within the forest,and promotes the growth of individual DBH and the accumulation of individual tree volume in eucalyptus trees.This study provides scientific basis for silvicultural practices and research on the targeted cultivation and sustainable management of large-diameter eucalyptus trees.

关 键 词：桉树 抚育采伐 光环境 单株材积 

分 类 号：S792.39[农业科学—林木遗传育种]