Database approach to calibrate growth and yield models in forestry production systems

Abstract

This study aimed to propose a step by step to prepare a database from permanent plots traditionally used in the growth and yield models for forest plantations typically planted in Brazil and designed to industrial processes like as pulp and paper, for example. To compose the adjustment were selected twenty-one plots with four measurements each. These twenty-one, four, were randomly selected, had their last measurement taken setting the database for validation of methodology described in this study. Five steps were proposed: 1 - Minimum Survival Rate; 2 - Minimum Uniformity Index; 3 - Increasing rate in a dominant and co-dominant average height; 4 - Increasing rate in basal area; 5 - Outlier removal for variable volume through the boxplot. The results showed about the robustness of the proposed method with improved precision by 7% ensuring greater accuracy, in addition to improving the stability of the order projection of 21%. So when we choose the methodology described in the study, this will provide the forest manager to build more realistic context planning.