林分断面积生长模型研究评述

The Review of Studies on Stand Basal Area Growth Model

林分断面积生长模型是林分生长和收获预估模型体系的主要组成部分。在对常用的断面积生长模型Ｒｉｃｈａｒｄｓ型和Ｓｃｈｕｍａｃｈｅｒ型分析的基础上，总结出断面积生长模型研究中应注意的４个问题：（１）选择的自变量应为３个，即立地质量指标、年龄和林分密度指标；（２）间伐林分模型应与未间伐林分模型同时考虑，进而详细介绍了用于间伐林分断面积预估的被压指数法；（３）间伐指标的构造需要伐前和伐后的林分因子；（４）提出的模型应具有多种期望性质，如机理性，渐近性，相容性，单调性和预估步长不变性。

Stand basal area growth model is a main component of stand growth and yield prediction model system.Based on the analysis of the common stand basal area growth model such as Richards model and Schumacher model,four important questions in study on stand basal area growth model are summarized as follows:(1)Three variables should be included in the model i.e.site quality index,age,and stand density index.(2)Thinned and unthinned stand growth model should be considered at the same time.Furthermore,the method of index of suppression used for basal area prediction for thinned stands is introduced in detail.(3)The construction of thinning index needs stand factors before thinning and after thinning.(4)The proposed model should have the desirable properties,such as mechanism, asymptotic property,compatibility,monotonicity,and the invariance for projection length.