Development of top height model and site index curves for Azadirachta indica A. juss

Abstract

This paper describes the development of top height model for stands of Azadirachta indica. The algebraic difference form of the Chapman–Richards equation is first fitted to the interval data of height–age data pairs resulting in an anamorphic system. Polymorphic site index curves were also developed using Ek’s extension of the Chapman–Richards function. Secondly, some commonly used models were compared for their goodness-of-fit and predictive ability in describing allometric relationships between volume, diameter and age. It has been observed that, in general, Chapman–Richards function may be used to model the relationships between these growth parameters.