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林木枯损率模型是树木生长与收获模拟系统中的一个重要组成部分。本文在充分研究国内外林木枯损率模型的基础上,根据北京市油松复位样地的数据,应用Logistic模型预测油松枯损率,模型自变量选择树木大小、竞争因子和林分密度等指标。研究结果显示:油松林木枯损率随径阶增加而呈U型分布,在5~15cm径阶时林木枯损率逐渐降低,之后枯损率又逐渐增加;枯损率随竞争激烈程度和林分密度的增加而增加。使用油松检验数据对建立的枯损率模型进行检验,发现该模型预测的油松枯损率与观测值之间没有显著差异。因此该模型可用于油松径阶和单木枯损率的预测。
The tree damage rate model is an important part of the tree growth and harvest simulation system. Based on the full study of the domestic and international forest plant loss models, based on the data of the resettled plots of Pinus tabulaeformis in Beijing, the logistic model was used to predict the percentage of the pine plantations. The model variables were tree size, competition factors and stand density index. The results showed that the damage rate of Pinus tabulaeformis forest was U-shaped with the increase of diameter. The loss of forest was decreased gradually when the diameter was 5 ~ 15cm, and then the damage rate was gradually increased. The rate of damage increased with the degree of competition and Stand density increased. Using the data of Pinus tabulaeformis test to test the established rate of damage model, we found there is no significant difference between the predicted rate of Pinus tabulaeformis damage and the observed value. Therefore, the model can be used for prediction of Pinus tabulaeformis and Shannon’s disease.