Local versus regional intraspecific variability in regeneration traits

Abstract

Intraspecific trait variability has a fundamental contribution to the overall trait variability. However, little is known concerning the relative role of local (e.g. disturbances and species interaction) and regional (biogeographical) processes in generating this intraspecific trait variability. While biogeographical processes enhance plant trait variability between distant populations, in fire-prone ecosystems, recurrent fires may have a preponderant role in generating variability at a local scale. We hypothesize that plants respond to the local spatio-temporal heterogeneity generated by fire by having a relatively large local variability in regeneration traits in such a way that overrides the variability at a broader biogeographical scale. We test this hypothesis by assessing the intraspecific variability in fire-related regeneration traits of two species (Cistus salviifolius and Lavandula stoechas) growing in fire-prone ecosystems of the Mediterranean Basin. For each species, we selected six populations in two distant regions, three in the east (Anatolian Peninsula) and three in the west (Iberian Peninsula). For each species and population, we analysed the following regeneration traits: seed size, seed dormancy and stimulated germination by fire-related cues (heat and smoke). To evaluate the distribution of the variability in these traits, we decomposed the variability of trait values at each level, between regions (regional) and between population within region (local), using linear mixed-effect models. Despite the biogeographical and climatic differences between regions, for the two species, intraspecific variability in regeneration traits was higher at a local (within regions) than at a regional scale (between regions). Our results suggest that, in Mediterranean ecosystems, fire is an important source of intraspecific variability in regeneration traits. This supports the prominent role of fire as an ecological and evolutionary process, producing trait variability and shaping biodiversity in fire-prone ecosystems.

New handbook for standardised measurement of plant functional traits worldwide

“…Poorter et al 2009). Species may therefore vary in which quantitative traits are stable across given gradients, so tests should be made before a trait is taken to be stable for a given species (Albert et al 2010(Albert et al , 2012Hulshof and Swenson 2010;Messier et al 2010;Moreira et al 2012).…”

Inter- and intra-population variability in physical dormancy along a precipitation gradient

“…Within species, a review of studies comparing populations in sites with different precipitations found that low rainfall during seed development favours the occurrence of PY (Hudson et al 2015 and reference therein). In addition, some degree of intra-population variability has been observed in regeneration traits (Moreira et al 2012;. Particularly, studies that analysed PY variation within populations found important differences among individuals (Pérez-García 1997; Lacerda et al 2004;Masaka & Yamada 2009).…”

Sequential Management of Commercial Rosewood (Aniba rosaeodora Ducke) Plantations in Central Amazonia: Seeking Sustainable Models for Essential Oil Production

“…Greater or lesser concentrations of some nutrients in the regrowing tissues occurs as a result of increased metabolic activity linked with the capacity of translocated nutrients from subterranean organs to above ground plant parts [59,60], which was observed in managed rosewood plantations.…”

“…This is especially important for rosewood seedlings which, in the first year of cultivation, need to be protected from directly incident sunlight in order to avoid photosynthetic photoinhibition [64]. In contrast, weed control is rarely required during with coppicing and canopy closure is achieved quickly [60].…”

“…The production of shoots after disturbances may be genetically-controlled [60], and is generally seen] in environments where fire or intense herbivory are common [32,71,[80][81][82]. Rosewood plants evolved in environments where natural fires are extremely rare, which rule out the possibility that the observed regrowth capacity of rosewood is the result of natural selection.…”