Work

Time since the last fire and climate seasonality reveal rhythmic and annual growth rates of Cerrado’s woody plants

Year: 2025

Type: article

Abstract: BACKGROUND AND AIMS: Growth patterns in tropical savanna woody plants remain poorly understood across their vast diversity of strategies and plant forms. Something still little known is whether tropical woody species exhibit rhythmic or seasonal growth. This study investigates growth rhythmicity in Cerrado woody species, focusing on their post-fire resprouting patterns and their relationship with rainfall seasonality and fire. METHODS: We analyzed the number and characteristics of growth units produced after fire events (2020 and 2021 wildfires) in 21 Cerrado species. Satellite imagery and morphological markers along stems - such as internode length and bud scars - were used to assess growth cycles. KEY RESULTS: Cerrado species exhibited clear annual growth, typically producing one growth unit per year, closely aligned with the rainy season. Morphological traits reliably marked these cycles. Primary growth was consistently greater in the first growth unit produced after fire, likely due to increased carbohydrate allocation and reduced apical dominance of previous existing stems. This enhanced growth may help position foliage above future flame zones, improving survival. As species exhibited an annual growth pattern, we observed synchrony between the number of growth units and the number of years since the last fire. CONCLUSIONS: Woody plants in the Cerrado grow through annual growth units formed from buds with preformed structures that elongate during the rainy season. The extent of this growth varies among species and individual life histories. Fire, a frequent disturbance, stimulates the production of larger growth units. This response indicates that woody plants can rapidly rebuild aboveground biomass after burning, likely supported by stored carbohydrates and the release of apical dominance. These patterns highlight the resilience of Cerrado vegetation. To deepen our understanding of tropical plant development, future work should relate growth units to species phenology, rainfall variability, and vegetation types.

Source: Annals of Botany

DOI: 10.1093/aob/mcaf324

Authors: Marco Antonio Chiminazzo, Alessandra Fidelis, Felipe Alvarez, Tristan Charles-Dominique