Dendrochronology and anatomy of woody structures in shrubs from natural grasslands of São Paulo state

Abstract

he present study aims to understand the growth dynamics of woody plants in tropical natural grasslands, highlighting the importance of dendrochronology for assessing the effects of climate and fire. Dendrochronology emerges as a crucial tool for comprehending plant dynamics over time, providing information on plant age, growth rates, past climatic variations, and disturbance histories (e.g., fire). In tropical regions, seasonality in precipitation is the main determining factor for the formation of annual rings in trees, while the occurrence of anomalous climatic events can lead to the formation of double or false rings. In this context, complementary methods such as X-ray densitometry and wood anatomy analyses are essential to assist in identifying annual boundaries of growth rings. Despite the consolidation of dendrochronology for tropical tree species, studies on shrubs and subshrubs are still scarce, especially in natural grasslands. This project aims to fill this gap by exploring, through techniques commonly used in anatomy of woody underground structures and dendrochronology, the estimation of plant age, the analysis of climate influence on radial growth, and plant response to fire. This study is expected to contribute to advancing knowledge about herbchronology, consolidating it as a research area in Brazil, and to elucidate pending scientific questions about the growth of small plants in natural grasslands under different climate and fire regimes, thus contributing to support management and conservation policies for these ecosystems. (AU)