Variações na estrutura da anatomia do lenho de árvores de Cmelina arborea Roxb. (Verbenaceae) de clima tropical seco e úmido na Costa Rica

In Costa Rica and tropical countries of Africa, Asia and Oceania the wood of Gmelina arborea trees is used for sawmill, as raw material for paper, wood-cement composites or panels. In these countries, the ecological climatic conditions of the areas of the gmelina reforestation programs are characterized by presenting differences in relation to the species natural habitat. However, the studies about the alterations induced in the wood anatomical structure of the trees in response to the new ecological conditions are scarce in the specialized literature. In this paper the wood anatomy of gmelina trees alterations from two climate conditions of Costa Rica were analyzed: dry tropical climate and wet tropical climate. For the multivariate analysis, the alterations can be related to the porosity type, vessels length and grouping, axial parenchyma disposition, rays width and frequency. The principal components results showed that the annual medium precipitation of the sampled sites is the source of variation of wood of gmelina trees in Costa Rica, besides the density of the plantation.