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本文提出了生长在俄勒冈州西南的同龄或异龄花旗松单株高生长率进行预报的五个模型,并对各自性能作出评价。其中三个模型已在花旗松中用过,第四个经过简单修改,而第五个是这次研究中通过多维曲线图和模拟的方法来发展的。有二个模型由年龄决定,另外三个与年龄无关。模型的发展使用了多维技术,它提供了同龄数据(1763个观测数)和同龄与异龄数据结合(2242个观测数)之间的最小均方差,并用241个观测数据组成的随机子集来验证五个模型。此外,这些用多维技术发展的模型仍有最小平均剩余差和最小均方差,模型的自变量是林冠郁闭和树冠比例。用优势木高生长方程作为预报潜在的高生长率,得出的模型与年龄无关,并能应用于同龄林和异龄林。这项多维技术最适用于复杂的曲面模型。
In this paper, five models for predicting the height growth of single-year-old Douglas-fir or Douglas-fir from southwestern Oregon were proposed and their performances were evaluated. Three of the models have been used in Douglas Fir, the fourth has been briefly modified, and the fifth has been developed in this study through multi-dimensional plots and simulations. Two models are age-dependent, the other three are age-independent. The development of the model used a multidimensional technique that provided the smallest mean squared error between peer data (1763 observations) and same age and anomaly data (2242 observations) and used a random subset of 241 observations Verify the five models. In addition, the models developed with multidimensional techniques still have the minimum mean residual difference and the minimum mean square error. The independent variables of the model are canopy canopy and crown ratio. The dominant height growth equation is used as a potential high growth rate prediction. The model obtained has nothing to do with age, and can be applied to the same age and heterogeneous forest. This multidimensional technique works best with complex surface models.