Resprouting as a key functional trait: how buds, protection and resources drive persistence after fire

Abstract

Contents 19I.20II.21III.21IV.27V.28VI.29VII.30VIII.3131References32 Summary Resprouting as a response to disturbance is now widely recognized as a key functional trait among woody plants and as the basis for the persistence niche. However, the underlying mechanisms that define resprouting responses to disturbance are poorly conceptualized. Resprouting ability is constrained by the interaction of the disturbance regime that depletes the buds and resources needed to fund resprouting, and the environment that drives growth and resource allocation. We develop a buds‐protection‐resources (BPR) framework for understanding resprouting in fire‐prone ecosystems, based on bud bank location, bud protection, and how buds are resourced. Using this framework we go beyond earlier emphases on basal resprouting and highlight the importance of apical, epicormic and below‐ground resprouting to the persistence niche. The BPR framework provides insights into: resprouting typologies that include both fire resisters (i.e. survive fire but do not resprout) and fire resprouters; the methods by which buds escape fire effects, such as thick bark; and the predictability of community assembly of resprouting types in relation to site productivity, disturbance regime and competition. Furthermore, predicting the consequences of global change is enhanced by the BPR framework because it potentially forecasts the retention or loss of above‐ground biomass.

Investigating the demographics and intrapopulation spatial patterns of the endangered Cycas megacarpa K.D.Hill in central Queensland, Australia

“…Species of the genus Cycas are typically longlived with mature individuals responding relatively well to disturbances, such as fires and drought, due to their ability to regenerate from apical or axillary buds along or at the base of the trunk (Watkinson & Powell 1997;Griffiths et al 2005;Clarke et al 2013). However, the probability of a seedling transitioning to an adult cycad is low, as a seedling does not store enough energy to recover from a disturbance (Watkinson & Powell 1997;Raimondo & Donaldson 2003).…”

Lignotubers in Mediterranean basin plants

“…Although the starch sustaining lignotuber bud growth is mainly stored in the roots (see Clarke et al 2013), the lignotuber starch might also contribute to energetically supporting resprouting (Canadell and López-Soria 1998). In fact, starch grains are very abundant in the lignotuber, and normally stored in the parenchymatous cells of the contorted xylem, but can also be found in the lignotuber cortex or in the stem pith-depending on the species (Carrodus and Blake 1970;Bamber and Mullette 1978;Molinas and Verdaguer 1993a).…”

“…This is a geographically widespread trait, occurring in very different lineages and ecosystems worldwide (Vesk and Westoby 2004a). There are different types of resprouting, depending on the location and amount of buds and their degree of protection (Bellingham and Sparrow 2000;Clarke et al 2013). In some woody species, basal resprouting occurs from a woody swelling at the root-shoot transition zone that conceals numerous buds and starch; this structure is called a lignotuber (James 1984 and references therein).…”

Do the structures of macaw palm fruit protect seeds in a fire-prone environment?

“…Fire also hampers certain biological processes, including fl owering, fruit production and development, and seed viability, dispersal, and germination (Trabaud 1987;Gignoux et al 1997). Plants may persist after fi re by resprouting from below-ground structures (Clarke et al 2013) or by having existing structures, such as thick bark, that provides protection to live meristems during the passage of fi re (Gignoux et al 1997;Pausas 2015).…”