帽儿山地区山杨次生林直径分布的研究

The study on the diameter distribution of the aspen secondary forest in Mao’er Mountain area

本文基于山杨(Popuplus davidiana D.)次生林固定标准地M712、M720的每木检尺数据,采用径阶直方图分析法和负指数方程对帽儿山林场天然山杨次生林的直径结构进行分析。研究结果表明:山杨次生林林分的直径分布较单一,径阶株数分布基本呈反J型曲线。负指数分布拟合曲线与实际分布比较贴近,在相邻径阶林木株数变动不算太大,尤其是小径级林木株数多时,用负指数分布拟合更为合适。

The study on the secondary forest of Populus tremuloides based on the per tree survey data of sampling plot M712,M720 have been done by P.tremuloides.In this paper,the diameter structure in P.tremuloides of the secondary forest in Mao’er Mountain has been analyzed by the diameterclass histogram and negative index distribution.The results show that the diameter distribution of P.tremuloides is more single than others,the distribution of the number of trees per diameter class is basically showed reversed J-shaped curve.Exponential distribution fitting is the actual distribution.Among the number of Size-class in the adjacent trees took up a small proportion,whereas the number of small diameter trees took up a larger proportion,especially many more trail-level trees,with a negative exponential distribution fit more appropriate.