资源环境科技发展态势分析平台

Abstract

Increasing demand for tropical hardwood and logging bans for natural teak forests have led to expanding teak plantations. Forest growth factors, briefly summarized in this chapter, may guide the establishment of new teak plantations. In contrast, existing timberland investments usually require accurate timber production estimations and projections that rely on mathematical models to inform silvicultural, managerial, and financial decisions. A thorough revision of the scientific literature on teak growth and yield modeling suggests that the state-space approach is perhaps the most suitable mathematical technique. Thus, the state-space approach model was used for projections. The system of equations, composed of the dominant height and basal area, is used to estimate stand production. A comprehensive but straightforward method that accounts for site productivity and thinnings allows for basal area projection over time, and diameter and volume estimation. Since teak timber value depends largely on the size of the logs extracted from the plantation, we also present a simplified but useful approach to estimate the average girth and to split the total commercial volume into timber product classes. An example wraps up this chapter with three basal area projections, thinning schemes, volume estimations, and timber product class distributions for the three financially feasible site index classes. Simulations indicate that at rotation age at year 20, stands end with 100 trees per hectare, quadratic mean diameter of 32 and 51 cm, total volume ranging from 112 to 153 m3/ha, and commercial volume ranging from 56 to 77 m3/ha, respectively, for the lowest and highest site index classes.