EQUATIONS MORPHOMETRIC SPECIES ANDIROBA (CARAPA GUIANENSIS AUBL) AND THE BRAZIL NUT (BERTHOLLETIA EXCELSA HBK) IN AGROFORESTRY SYSTEMS IN THE MUNICIPALITY OF PORTO VELHO, RONDÔNIA

Abstract

Andiroba (Carapa guianensis Aubl) and the Brazilian nut (Bertholletia excelsa HBK) are considered key species in the maintenance of standing forest in areas susceptible to degradation and  deforestation in the Amazon. Both species have shown great potential for growth and production in homogeneous plantations and agroforestry systems (SAF's) in the Amazon, the extraction of timber and non­timber forest in these environments is possible since informed the environmental agency responsible. This study was conducted in environments agroforestry (SAF's) of Project RECA (Economic Reforestation and Compacted Syndication), in the Municipality of Porto Velho, Rondônia. We sampled 25 individuals from Andiroba and 40 individuals from the Brazil  nut with DBH > 10 cm (diameter at breast height, measured at a distance of 1.30 meters above the ground), arranged randomly in 20 farms (1 ha each) considered productive age (15­18  years). We tested 99 equations of the morphometric variables as a function of DBH these two species. We used a linear regression analysis by the procedure "stepwise". The best fitting was obtained with the following models: Crown Diameter (DC) = β 0 +β 1 (DBH 2 )+ε (R 2 aj = 0,86; Syx = 0,698) and Canopy Proportion (PC) = β 0 +β 1 (1/DBH 3 )+ε (R 2 aj = 0,73; Syx = 6,771) for  Andiroba and Canopy Área (AC) = β 0 +β 1 DBH 3 +ε (R 2 aj = 0,73; Syx = 20,407) and DC = β 0 +β 1 (DBH 2 )+ε (R 2 aj = 0,67; Syx = 1,288) for Brazilian nut. The conclusion is that the equations morphometric adjusted proved accurate and efficient in understanding the morphometric studied as a function of DBH.