Dendroecological Studies with Cedrela odorata L., Northeastern Brazil

Abstract

Northeastern Brazil is home to the Caatinga Forest, characterized as a Tropical Dry Forest (TDF), and the Dense Ombrophilous Forest (the Atlantic Forest) predominates near the coast. In the Caatinga, the climate is semiarid, with <600 mm of mean annual precipitation and a mean annual air temperature of 27 °C ± 6 °C. The precipitation presents a seasonal pattern, with a rainy season concentrated in the first half of the year and at least 6 months of dry season, with volumes <50 mm/month. The climate in the Atlantic Forest has a milder air temperature and a mean rainfall of 1450 mm/year. In both regions the tree species, Cedrela odorata L., widely studied in dendrochronology, presents populations in farms, with several individuals per hectare. In recent decades, 10 chronologies of C. odorata have been produced and compared to precipitation and other environmental factors, and their competition with lianas and support of the herbivorous process has been noted. This chapter presents the potential of C. odorata for dendrochronology in Northeastern Brazil; the anatomy of true rings with marginal parenchyma associated with vessels differed from the false rings by the absence of vessels. Absent rings were also observed. Nine chronologies had correlations above the critical level of 0.51 (0.51?0.79) and sensitivity between 0.547 and 0.771. The correlation between all series (rbt) of all chronologies had values between 0.27 and 0.68 and expressed population signal (EPS) above 0.85 (between 0.88 and 0.98). In both biomes, several populations of C. odorata have resulted in climate-related chronologies that showed the seasonal rainfall from May to July induces metabolism and growth rings formation. We also presented the methodology used for tropical dendroecology studies and the relationship between plant growth and environmental conditions.