Seasonality affects the below‐ground bud bank dynamics of the Cerrado

Abstract

Question: How does seasonality affect the below-ground bud bank dynamics in open savannas from the Cerrado and the density of below-ground bud-bearing organs?As the Cerrado is subject to marked seasonality, many herbaceous plants may lose their above-ground biomass during the dry season, and regenerate it later in the rainy period through resprouting from below-ground buds. Herein, we tested the hypothesis that seasonality may directly affect bud bank dynamics and below-ground bud-bearing organs, with a larger bud bank size and higher densities of below-ground organs in the rainy season.Location: Open savannas of the Cerrado, southeastern Brazil. Methods:The bud bank was sampled in three open areas of the Cerrado. In each area, 10 plots were established, and, within each plot, the biomass was sampled to 10 cm below-ground level. In the lab, buds and below-ground organs were counted. We fitted generalized linear mixed models (GLMM) to test the differences in the bud bank and the below-ground organ densities between the dry and rainy seasons. Results:The bud bank size was smaller in the dry season. Buds found in the dry season suggest they were developed in the rainy season and remained dormant, not forming new shoots. Non-woody rhizomes of caespitose grasses were more abundant during the rainy season. Xylopodia and woody rhizome densities were not significantly affected by seasonality.Conclusions: Bud bank dynamics in the Cerrado is affected by seasonality. There is a decrease in bud bank density in the dry season, suggesting that buds were developed into new branches in the rainy season, but not all of them develop into new shoots in the same season. Thus, the bud bank evaluated in the dry season probably is formed by an accumulation of dormant preformed buds, highlighting the occurrence of a resprouting dynamic of native species of the Cerrado in the rainy season.

Changes in bud bank and their correlation with plant community composition in degraded alpine meadows

“…For example, Russell et al (2019) found that grass bud renewal activity is stimulated by burning. Similarly, Alexandre et al (2022) found that seasonal fires play a vital role in bud bank dynamics in the Brazil's Cerrado savannah and that bud bank densities decrease in the dry season. Some buds can develop into new branches in the rainy season.…”

“…Bud banks are also reduced in number as mean precipitation decreases (Dalgleish and Hartnett, 2006). Furthermore, fire has positive effects on regulating bud bank density (Benson et al, 2004;Dalgleish and Hartnett, 2009;Russell et al, 2019;Alexandre et al, 2022). For example, Russell et al (2019) found that grass bud renewal activity is stimulated by burning.…”

Responses of bud banks and shoot density to experimental drought along an aridity gradient in temperate grasslands

“…Plant dynamics and primary productivity almost entirely driven by asexual reproduction via below‐ground bud banks in perennial grasslands (Benson & Hartnett, 2006; Klimešová & Klimeš, 2007). Below‐ground bud banks play a key role in plant population regeneration, community dynamics, and ecosystem functioning following disturbances and environmental change (Ferraro et al, 2022; Ott et al, 2019; Siebert et al, 2019). As a primary resources of above‐ground regrowth, the ability of bud banks to withstand drought can drive accelerated or delayed ecosystem resilience once drought ceases (Dalgleish & Hartnett, 2006, 2009; Qian et al, 2022).…”

“…Below-ground bud banks play a key role in plant population regeneration, community dynamics, and ecosystem functioning following disturbances and environmental change (Ferraro et al, 2022;Ott et al, 2019;Siebert et al, 2019). As a primary resources of aboveground regrowth, the ability of bud banks to withstand drought can drive accelerated or delayed ecosystem resilience once drought ceases , 2009Qian et al, 2022).…”