Ajuste e avaliação da estimativa volumétrica para Lecythis lurida (Miers) S.A Mori na Floresta Nacional do Tapajós

Abstract

The objective of the present study was to evaluate the efficiency of volumetric adjustments for Lecythis lurida in the Tapajos National Forest. The data came from 100% inventory and and rigorous species counting in UPA 8. 301 trees were selected from Lecythis lurida with 50 cm ≥ DAP <150 cm, where 8 volumetric models were fitted. For the choice of the best equation, we analyzed the significance of the coefficients by the t test, adjusted coefficient of determination, standard error of the estimate, and factor of inflation of the variance to verify situations of multicollinearity, graphical analysis and histograms of residues. For the validation of the best equation, the actual and estimated volume were compared by the chi-square test at 95% probability. The combined Spurr variable models, Husch, Schumacher Hall and Spurr - both logarithmized presented significance of all parameters by the t test. Regarding the precision parameters, the Spurr combined variable models, Schumacher Hall and Spurr logarithmized presented the best values. After the removal of outliers is clear the improvement in the parameters of precision of the models. In relation to the graphical distribution of the residues, the Schumacher and Spurr logarithmized models presented similar results, but when analyzing the other criteria of selection of the best model, Spurr combined variable was considered the most adequate to estimate the volumetry of the species in the area for its simplicity of application. The selected equation generated estimates that did not differ statistically with real volume according to the chi-square test.