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Age and radial growth rate are key data on understanding some aspects of tropical forest dynamics and ecology. In species that produce annual tree rings, tree-ring analysis allows the most precise estimate of these two parameters. The present study assessed the age and radial growth rate of three Hymenaea species inhabiting four of the six biomes found in Brazil. Out of these four biomes, two harbor the largest rainforests in South America, the Amazon Forest on the west and the Atlantic Forest in the east. The Cerrado biome is an open and seasonally drier vegetation found between them and the Pantanal is a wetland in the west. The H. courbaril species inhabits almost the entire Neotropical lowlands while H. parvifolia and H. stigonocarpa are restricted to the Amazon and Cerrado biomes, respectively. To investigate these species dynamics within different biomes, age and radial growth rate were calculated for 217 trees through tree-ring analyses. The oldest H. courbaril and H. parvifolia trees were 316 and 371 years old, respectively, while H. stigonocarpa trees were considerably younger, up to 144 years old. Hymenaea courbaril trees showed the widest variation in average growth rate, from 1.00 to 6.63 mm per year, while the other two species showed a narrower variation from 0.89 to 2.81 mm per year. The studied populations presented distinct trends in the lifetime growth pattern that seems to be related to the biome of provenance. Overall, trees from the Amazon forest showed a trend of increasing growth rate up to about 100 years followed by a decreasing of it, while trees growing in the Pantanal and Atlantic forest showed only decreasing growth rates. In the Cerrado, trees showed a constant pattern of growth rate up to 50 years followed by a clear decline. It is important to highlight that different species of Hymenaea showed similar growth trends within the same biome. In larger trees, the average growth rate is lower in the Cerrado, which is characterized by deeper water tables and more dystrophic soils while the growth rates in the Amazon and Atlantic Forests are 60 % and 79 % higher, respectively. This study represents one of the most comprehensive datasets of trees age and growth rate of tropical congeneric species under such large geographical range. Zusammenfassung: Alter und Zuwachsraten von tropischen Bäumen liefern wichtige Daten über das Verständnis verschiedener Aspekte bezüglich der Dynamik und Ökologie von tropischen Wäldern. Bei Baumarten, welche jährliche Zuwachsringe ausbilden, ermöglicht die Jahrringanalyse eine genaue Untersuchung dieser beiden Parameter. Die vorgestellte Studie analysiert Alter und radiale Zuwachsraten von drei Hymenaea Arten, in vier der sechs Biome Brasiliens. Von diesen Biomen gehören zwei, der Amazonas Regenwald und der Atlantische Regenwald, zu den größten Regenwäldern Südamerikas. Das Biom Cerrado ist eine offene Savannenlandschaft, welche eine saisonale Trockenzeit aufweist. Bei dem Pantanal handelt es sich um ein Feuchtgebiet. Die Art H. courbaril ist in fast allen neo...

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A tropical tree-ring study is presented using 36 specimens of Cariniana estrellensis from the Mata Atlântica Biome within the State of São Paulo: Caetetus and Carlos Botelho. We aimed to assess the suitability of this species for chronology building, as well as for dendroclimatological studies, with the help of its lifetime growth trajectories. Cariniana estrellensis forms visible tree rings with a dense sequence of parenchyma bands at the end of the latewood, followed by a relatively distant sequence of parenchyma bands in the subsequent early wood of a tree ring. However, it was impossible to establish a chronology, solely by tree-ring width measurements and crossdating, for a number of reasons, including sequences of problematic wood anatomy, abundance of wedging rings and probably missing rings. Therefore, building a robust chronology for this species requires a multi-parameter approach, however, no experience is currently available. Therefore, to reveal possible climate-growth relationships for Cariniana estrellensis at both sites, we tested to correlation analyses of microclimatic conditions with tree growth and investigated patterns of lifetime growth trajectories. Annual precipitation is over 1300 mm at both sites, with the dry season primarily between June and August. Both sites showed clear differences in their microclimatic regime and topography. Overall, light availability is the most likely crucial factor for the studied species. A significantly lower photosynthetic active radiation and daily photoperiod was found at Carlos Botelho by the strong influence of orographic rainfall, foggy conditions and shade caused by the adjacent mountain chain. Consequently, trees at this site generally showed a lower average annual growth rate as compared to the Caetetus site with differences between juvenile and mature growth phases remaining nearly constant throughout their lives. In contrast, trees from Caetetus had less consistent growth phases, with increased growth after the juvenile growth phase. Thus, it can be concluded that dendroclimatological studies using growth characteristics have the potential to clarify the generally complex stand dynamics of Cariniana estrellensis. However, the development of tree-ring chronologies, based on tree-ring width analyses of cores or discs is nearly impossible. Zusammenfassung: Eine tropische Baumringstudie wurde mit Hilfe von 36 Individuen von Cariniana estrellensis an den Standorten Caetetus und Carlos Botelho im Atlantischen Regenwald des Bundesstaates São Paulo (Brasilien) durchgeführt. Ziel war es, die Eignung von Cariniana estrellensis zur Erstellung exakter Jahrringchronologien zu überprüfen sowie die Eignung für dendroklimatologische Untersuchungen mit Hilfe von lebenslangen Wachstumsverläufen zu bewerten. Cariniana estrellensis bildet optisch sichtbare Jahrringgrenzen aus, die durch den Wechsel von eng aneinandergereihten Parenchymbändern im Spätholz, gefolgt von weniger dicht gestaffelten Parenchymbandabfolgen im Frühholz gekennzeichnet sind. Jedoch war es aufgr...

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