【摘要】 本文以Richards函数为基本模型,讨论了不相交多形地位指数曲线的拟合。解决了标准年龄时树高与指数值不一致的问题;给出了根据树高和年龄求指数的实用迭代公式;探讨了标准年龄不同,指数曲线形状是否会变化的问题;最后讨论了本文所用的杉木多形地位指数曲线模型的一些特性。更多还原

【Abstract】 Richards function was used as a basic model to study the non-intersection polymorphic site index curve, which solved the problem existed while the height of the tree was not uniform with the site index at standard age in plantations of Chinese fir and Masson pine. A practical site index substitution formula was worked out to get the site index according to the height and age of the tree. The problem that whether site index will chang at different standard age or not was discussed. Finally, a general discussion on properties of the polymorphic site index curve equation for Chinese fir was made.更多还原