不同林型的兴安落叶松混交林直径结构研究

Study on Diameter Structure of the Larix gmelinii Mixed Forests

在内蒙古大兴安岭根河林业局潮查林场兴安落叶松的3个不同森林类型的混交林中各设置1个样地进行调查,对其径阶株数分布特征进行分析,利用负指数分布函数表达其直径结构,并采用q值理论检验直径分布是否合理。研究结果表明,适宜异龄林直径分布模拟的为2号样地,其q值为1. 486,拟合效果较好; 1号和3号样地不适于异龄林直径分布模拟,q值分别为1. 622和1. 892,拟合效果不理想。3种森林类型的直径结构呈倒"J"型曲线分布,即小径阶的林木数量较多,随直径的增加,林木数量逐渐减少,到达一定程度后趋于平稳。

The sample plots for 3 different forest types of Larix gmelinii mixed forest in Tshaocha Forest Farm of Genhe Forestry Bureau of Greater Khingan Mountains in Inner Mongolia were investigated. The diameter distribution of the number of plants was analyzed,and the diameter structure was expressed by using the negative exponential distribution function,and the q-value theory was used to test whether the diameter distribution was reasonable.The results showed that the suitable diameter distribution of different-aged forests was sample No.2 with the q value of 1.486, which had a good fitting effect.The No.1 and No.3 plots were not suitable for the simulation,with the q values of 1.622 and 1.892,respectively.The diameter structure of the three forest types presented a reverse J-curve distribution, that was, the trees were mainly small diameter class, and the number of trees gradually decreased with the increase of diameter, and then leveled off to a certain extent.