异龄针阔混交择伐林均衡曲线的确定方法——以金沟岭林场样地数据为例

Methods for determining equilibrium curve of uneven-aged selection theropencedrymion——Taking sample plot data in Jingouling Forest Farm as a case

采用金沟岭林场30块样地8次观测数据,对3种异龄针阔混交择伐林均衡曲线确定方法进行比较。同时,引入方差值对现有林分的直径分布进行结构稳定性判断,通过非线性规划模型对现有的直径分布进行结构优化调整,并利用矩阵法预测下一周期的直径分布。结果表明:De Liocourt均衡曲线是一个理想状态的曲线;López均衡曲线在不考虑采伐或各径级采伐率相等的情况下比较适用;Schütz均衡曲线既考虑了树木的生长信息,也包括了林分的采伐和枯损信息,较好地描述了林分的真实情况;分别以这3种均衡曲线为标准,对现有林分的直径分布进行结构优化调整后,下一周期的直径分布趋向于稳定。

We compared three equilibrium models for the uneven-aged selection theropencedrymion with eight times of collected observed data at 30 sample plots in Jingouling Forest Farm of Jilin Province. Firstly we determined the structural stability of actual stand diameter distribution with variances, and then optimally restructured existing diameter distribution by non-linear programming model, and finally predicted the diameter distribution in the next period by dynamical matrix model. The result showed that： De Liocourt＇s equilibrium curve was an ideal diameter distribution ; L6pez＇ s equilibrium curve fitted well if the harvest was not considered or the harvest rate equaled in each diameter class; Schatz＇ s equilibrium curve had the best performance to describe the real situation of forest, in which not only harvest but also mortality information were considered. After optimally restructuring the actual diameter distribution with the three equilibrium curves, the predicted diameter distribution tended to be stable in the next period.