青冈栎次生林林木综合竞争压力指数研究

摘要

以研究青冈栎林木竞争、掌握青冈栎林分竞争结构规律、为评价林木竞争压力状况提供新方法为目的.以中南林业科技大学芦头林场青冈栎次生林为研究对象,构建青冈栎优势木冠幅模型,并采取平均离差百分数调整法对模型进行调整得到青冈栎自由树冠幅模型.分别利用样地偏移法和影响力因子判别法确定对象木和竞争木.基于单木影响圈构建单木影响体,同时结合竞争压力指数(CSI)提出综合竞争压力指数(C-CSI)概念.分析得到CSI、C-CSI以及简单竞争指数CI与胸径均为指数函数关系.三个竞争指数均表明林木胸径越大其受到的竞争压力越小,但综合竞争压力指数C-CSI比CSI和CI有更高的相关性,说明竞争指数考虑树高的必要性,用C-CSI评价林木在林分中受到的竞争压力要优于CSI和CI.%The aim of this study is to learn the trees competition and the competition structure law of forest stand of Cyclobalanopsis glauca,provide a new method forevaluating trees competition.This study used the Cyclobalanopsis glauca secondary forest of LuTou tree farm as the research object,builtthe open-growing tree canopy model of Cyclobalanopsis glauca from dominant trees canopy model by referencing the method of average deviationpercentageadjustment.Determined the object trees by sample area migration method and determined the competitive trees by the influential factor decision method.Built Cylinder of influencebase on the Circle of influence,came up with the comprehensive-competition stress index.The relation between CSI、C-CSI、CI and DBH were exponential function.The three competition indexes showed that the bigger the DBH was,the smaller the value of competition index was,C-CSI got highercorrelation than CSI and CI,it showed the necessity for competition indextaking into account the height of tree,and the C-CSI was better than CSI and CI when evaluating the trees competition.