The objective of this study was to propose a method for stratification of an unexplored terra firme dense ombrophylous forest into classes of volumetric stocks, by using the techniques of cluster and discriminant analysis. The research was carried out at the Forest Management Unit (FMU) in Tracajás Farm (02º 35'53" S and 47º 47'10"W), owned by Nova Era Agroflorestal, in Paragominas, Pará, Brazil. An census (100%) was accomplished in which the volumes of commercial whole-tree with dbh > 45 cm were estimated for 55 commercial species in 49 stands 10 ha each. The estimated volumes of individual commercial whole-trees were organized in a increasing order. A X-matrix was built, in which each variable x ij represented the i-th volume classified in the j-th stand. This X-matrix was the input for the cluster and discriminant analysis. The application of the cluster analysis resulted in hierarchical clusters of the stands in stock classes. The analysis of the dendrogram allowed the stratification of the forest in three homogeneous and distinct groups, denominated classes of volumetric stock I, II and III. The discriminant analysis pointed out that 100% of the stands were correctly classified. The multivariate classification of the forest into homogeneous classes of volumetric stocks showed to be an efficient method for stratification of uneven-aged forests, which can be constituted by extracts, compartments, site classes and annual production units.
Tropical forest; stratification; multivariate analysis; stock classes
