地位指数法是当前立地质量评价中广泛采用的一种评定方法。在同一立地上,实现不同树种地位指数之间的转换,建立地位指数相关关系模型有助于立地质量的评定。然而,地位指数相关关系模型中其自变量和因变量均存在度量误差,所以采用常规的回归模型不合理或使用不便利。利用线性度量误差模型,以湖南省雪峰山杉木和马尾松地位指数为研究对象,建立了杉木和马尾松地位指数相关关系模型,并进行精度检验和模型适用性检验,其平均相对误差为5.391%,模型精度比较高。研究结果有助于不同树种间的立地质量评定。
Site index is an effective method that has been widely used to evaluate site quality at present.The study of the correlation among site indexes of different tree species stands and establishment of correlation model of different site indexes in the same site for several tree species could be useful for predicting one site index(dependent variable) on condition that the other site index(independent variable) is known,and is propitious to evaluate site quality.There were measurement errors in independent variable and dependent variable of site indexes correlation model,so general regression model is not reasonable for it.Based on site indexes of Cunninghamia lanceolata and Pinus massoniana stand at Xuefeng mountain in Hunan province of China,the measurement linear model of them was established.The precision and accuracy tests of model were performed.The model precision is high and t mean relative error of it is 5.391 percent.This result would be help to evaluate site quality of different trees species.