兴安落叶松中幼龄天然林空间利用特征及影响因子  

Characteristics and impact factors of space utilization of young and middle-aged natural Larix gmelinii forests

作　　者：玉宝 YU Bao(National Academy of Forestry and Grassland Administration,Beijing 102600,China)

机构地区：[1]国家林业和草原局管理干部学院,北京102600

出　　处：《浙江农林大学学报》2020年第3期407-415,共9页Journal of Zhejiang A&F University

基　　金：“十二五”国家科技支撑计划项目(2012BAD22B0204)。

摘　　要：【目的】以大兴安岭过伐林为研究对象,界定林分空间利用,提出林分空间利用率计算方法,从林分水平空间、垂直空间、综合空间利用率3个方面分析天然林空间利用规律。【方法】利用14块样地数据,应用相关分析和逐步回归分析方法揭示影响林分空间利用率的主要因子。【结果】14块样地林分水平空间利用率、垂直空间利用率和综合空间利用率分别为62.5%~85.9%、31.2%~65.5%和50.1%~68.7%;平均水平分别达73.6%、46.0%和59.2%;随着林分生长,林木数量、个体大小、分布格局不断被调整,林分水平空间利用率发生变化;林分水平空间利用率与样地林木株数、更新密度和林木聚集系数极显著正相关(P<0.01),与林分蓄积量显著负相关(P<0.05),与林分平均胸径极显著负相关(P<0.01);不同生长阶段的林分垂直空间大小不一,随着林分生长,林分高度、各层林木株数和高度逐渐被调整,林分垂直空间大小和空间利用率发生动态变化;林分垂直空间利用率与更新层高极显著正相关(P<0.01),与样地林木株数、更新密度、林木聚集系数显著负相关(P<0.05),与垂直层次数、主林层高、演替层高、主林层与更新层高差、演替层与更新层高差、更新层株数极显著负相关(P<0.01);林分综合空间利用率受水平和垂直结构两方面因素影响,与林分密度、主林层株数显著正相关(P<0.05),与垂直层次数、演替层高显著负相关(P<0.05),与主林层高、主林层与更新层高差极显著负相关(P<0.01)。【结论】随着林分生长,林分空间大小和空间利用率发生动态变化。影响林分水平空间、垂直空间、综合空间利用率主要因子分别为更新密度、演替层与更新层高差、主林层高、林分密度和演替层高。提高林分空间利用率,优化林分结构,需要采取兼顾水平结构和垂直结构多种因子的立体技术措施。在林分不同生长阶段合理调控�[Objective]Taking the over-cutting forest in Daxingan mountains as the research object,this study aims to define space utilization of forest,propose the calculation method for space utilization ratio and analyze space utilization law of natural stands from three aspects:horizontal space,vertical space and comprehensive space utilization of stands.[Method]Using the data of 14 sample plots,correlation analysis and stepwise regression analysis were applied to reveal the main factors influencing space utilization ratio of forest stands to provide theoretical basis for the structure optimization of natural stand,its tending and management.[Result](1)The utilization ratios of horizontal space,vertical space and comprehensive space in 14 plots were 62.5%−85.9%,31.2%−65.5%and 50.1%−68.7%,respectively.The average levels were 73.6%,46.0%and 59.2%,respectively.(2)With the growth of forest stands,the tree number,individual size and distribution pattern were constantly adjusted,and utilization ratio of horizontal space also changed.The horizontal space utilization ratio of stands was significantly positively correlated with tree number,renewal density as well as tree clustering coefficient(P<0.01),negatively correlated with stand stock(P<0.05)and stand mean breastheight diameter(P<0.01).(3)The vertical space size of stands at different growth stages varied.When stand growth,stand height,tree number and height of each layer were adjusted gradually,the vertical space size and space utilization ratio of forest stands changed dynamically.The utilization ratio of vertical space of stands had extremely significant positive correlation with height of renewal layer(P<0.01),significant negative correlation with tree number,renewal density and forest accumulation coefficient(P<0.05),and extremely significant negative correlation with the number of vertical layer,height of main forest,height of succession,height difference between main forest and renewal layer,height difference between succession layer and renewal layer,and number

关 键 词：林分空间利用 影响因子 林分空间填充 林分结构 结构优化 过伐林 大兴安岭 

分 类 号：S757[农业科学—森林经理学]