武夷山区域南方铁杉种群密度效应模型

Study on the density effect model of Tsuga tchekiangensis population in Wuyi Mountain area

利用种群密度效应模型N=exp(aln2S+blnS+c)对南方铁杉种群密度变化过程进行拟合,其中N为单位面积株数;S为林分单株平均胸高断面积;a、b、c为待定参数,模型拟合结果为N=exp(4.38515ln2S+11.94198lnS+10.73876),相关系数r=0.8895,拟合效果较好;同时,对伴生树种的种群密度进行拟合,发现伴生树种的相关系数r=0.5532,拟合效果不佳。模型模拟结果表明,南方铁杉种群密度变化机制既受其自疏作用的影响,也受其伴生树种他疏作用的制约,但自疏是影响南方铁杉种群密度减少的主要原因。模型较好地描述了南方铁杉种群密度效应规律,可应用于指导其密度调节与控制。

The density effect of Tsuga tchekiangensis population was analyzed by the theoretical model describing the whole density change process of plant population,i.e.,N=exp（aln^2S＋blnS＋c） where N and S represent population density and mean basal area of at breast height respectively,and a,b,c are parameters.The result of which was described as N=exp（4.385 15ln^2S＋11.941 98lnS＋10.738 76） r=0.889 5.At the same time,there is a poor correlation r=0.553 2,by simulating the population density of species associated species.Model simulation results showed that the population density of T.tchekiangensis not only influenced by self-thinning effects,but also by associated tree species.The impact of self-thinning was primarily due to decreasing of T.tchekiangensis population density.The simulated results showed that the model fitted well observed data from T.tchekiangensis population.Therefore it is very useful in practice,which will provide a scientific basis for density management of T.tchekiangensis population.