落叶松人工林威布尔分布参数与林分因子模型的研究

以落叶松人工林２５８块标准地为材料，求解了各标准地威布尔分布概率密度函数参数。多数普遍随上层高、直径的增大而增大，随密度增大而降低，据此构建林分因子与参数、参数间拓广Ｒｉｃｈａｒｄｓ模型。通过精度、显著性、适用性、断面积平均直径等检验，参数模型与密度、上层高、直径模型结合最佳。模型可动态预测林分株数分布，为森林抚育间伐设计各生长阶段间伐方法、强度，预测林分蓄积等提供依据。

WEIBULL DISTRIBUTION PARAMETERS AND STAND FACTOR MODEL OF LARIX PLANTATION

Taking 258 plots of Larix plantation as the experimental material, probabilitydensity function parameters fitted to Weibull distribution of every plot were calculated.It was found that the parameters increased with increasing of upper height anddiameter, but decreased with increasing of density. Thus, the Richards model extendedrelations between stand factor and parameter, among parameters was established. Thecombination of parameter model with density, upper height, and diameter model wasdetermined the best, after precision, significance, applicability, and the averagediameter of basal area were tested. The tree distribution of a forest stand can bepredicted by the model. And the model can provide the base for intermediate cuttingsat different growth stages and intensities, and predicting stand volume.