Reliable estimates of radial growth for eight tropical species from seasonal-dry forests in Bolivia based on wood anatomical patterns

Abstract

The application of dendrochronological methods based on the precise delimitation of annual bands in tropical trees is vital for implementing precise management practices. This study described the most prominent anatomical features associated with the presence of annual tree rings in Amburana cearensis, Cedrela fissilis, Platymiscium ulei, Centrolobium microchaete, Hymenaea courbaril, Anadenanthera colubrina and Ficus boliviana, eight important timber species from the dry tropical Cerrado forest in Bolivia, South America. Initial or marginal parenchyma is the most consistent pattern delimiting annual bands in six of the eight selected species. Wedging and false rings, but more frequently the lack of circular uniformity in ring width, were recorded in most species. Differences in the number of rings between radii from a crosssection were used as reasonable estimates of dating error associated with each species. The rates of growth of cross-dated and non-cross-dated trees with dating errors relatively lower (i.e. around four missing rings per century) were not significantly different, suggesting that the rates of growth from non-cross-dated trees could also be used for complementing the estimates of radial growth derived from cross-dated trees. Given the difficulty of properly dating some tropical woods, measuring growth rates using a combination of cross-dated and non-cross-dated tree rings could provide reliable information to the sustainable forest management in the tropics.