滇中地区云南松林分胸径生长模型

应用云南省五期森林资源连续清查样地数据,用非线性回归方法构建云南松林分生长模型,并分析各环境因子对云南松林分胸径的综合影响。结果表明:(1)林分径阶株数随胸径的增大整体呈倒"J"型分布,林分直径分布曲线向左偏斜程度较大,且呈低峰态分布,分布相对离散;(2)林分胸径最优生长模型为坎派兹模型,决定系数(R2)和均方根误差(RMSE)分别为0.648和3.384,预估精度(P)为96.53%;(3)林龄、地位级指数、风速、郁闭度和相对湿度等是对林分平均胸径影响较为重要的因子。

Stand Diameter Growth Model of Pinus yunnanensis in Ce ntral Yunnan,China

The growth model of Pinus yunnanensis forest established by nonlinear regression method was used to analyze the com-prehensive influence of environmental impact factors on DBH of Pinus yunnanensis, with the data from the five phases of Continuous Forest Inventory data of Yunnan Province.The result showed that:(1)The trees of stand diameter class overall shaped like a"J"with the diameter increasing.The stand diameter distribution curve was larger to the left and the relative-ly discrete with low kurtosis distribution.(2)The optimal growth model of diameter was Gompertz model,and the maximum determination coefficient R2 was 0.648,the minimum root mean square error was 3.384,and the predict precision was 96. 526%.(3)Age,status index,wind speed,canopy density and relative humidity were the important environmental impact factors for the average DBH of the stand.