Comparative analysis of anatomy and micro-densitometry of the growth rings of hardwoods and conifers, with emphasis on dendrochronology

The seasonal climate induces variations in the activity of cambial meristem reflecting in significant changes in the wood anatomical structure and formation of the growth rings. In this study wood samples of 17 species were selected from the Wood Collection of the Anatomy and Wood Identification Laboratory, Department of Forest Sciences, featuring its macro and microscopic anatomical wood structure and the analysis by X-ray densitometry. The wood anatomical characteristics, with emphasis on the growth rings, indicated the tree species with the greatest potential for dendrochronology, especially those of the Family Fabaceae-Caesalpinioideae. A wood density profile and the delimitation of the growth rings boundaries were obtained by X-ray densitometry. This paper emphasized the importance of joint application of wood anatomy and X-ray densitometry as support to dendrochronology of tropical and subtropical tree species in order to determine their age and growth rate, their technological characterization and sustainable forest management.