以北京西山林场低山区调查的89块侧柏人工林样地数据为基础,采用一元线性回归模型、多元线性回归模型、其它模型对不同立地条件下的侧柏单木冠幅预测模型进行研究。结果显示:低山阳坡的侧柏人工林单木冠幅分布范围大于低山阴坡的,且低山阳坡的平均冠幅为3.05m也显著高于阴坡的2.83m;多元线性回归模型对低山阳坡和低山阴坡的侧柏人工林单木冠幅生长拟合精度最高,R2值分别为0.751和0.770;采用未进行建模的数据对筛选出的多元线性回归模型进行T检验,发现实测值和预测值差异不显著,残差服从正态分布,拟合效果良好。研究结果可对低山区侧柏人工林的冠幅生长动态进行精确预测,为侧柏人工林经营管理的数字化、动态化、精确化提供理论依据。
Individual crown width growth models for Platycladus orientalis plantation in Beijing low mountain area were established by linear regression model,multiple linear regression model and other models in accordance with data measured from 89 sample plots.The results show that the crown distribution range of Platycladus orientalis plantation in low mountain sunny slope is larger than that of shady slope,and the average crown width is significantly higher than that of shady slope.The forecast accuracy of multiple linear regression model is highest,the R2 values are 0.751 and 0.770 respectively.T test of the multiple linear regression model reveals that the actual value is fitted well with the predicted value.The results could be applied to the crown width growth forecast of Platycladus orientalis plantations in Beijing low mountainous regions to provide a theoretical basis for the scientific management of Platycladus orientalis plantation.
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