Rapid evolution of flower phenology and clonality in restored populations of multiple grassland species

Abstract

Restoration of terrestrial ecosystems often requires re-introduction of plants. In restored sites, the plants often face environment that differs from the one in natural populations. This which can affect plant traits, reduce performance and impose novel selection pressures. As a response, restored populations might rapidly evolve and adapt to the novel conditions. This may enhance population survival and contribute to restoration success, but has been rarely tested so far. Here, we focused on populations of three grassland species restored 20 years ago (Galium wirtgenii, Inula salicina and Centaurea jacea) by the transfer of green hay, and compared them with populations that were source of the hay. We measured plants both in-situ, and in common garden under control and three stress conditions. In-situ, restored and natural populations differed in flowering phenology in two out of the three species. In the common garden, plants of the restored population flowered earlier (in Galium) or showed increased plasticity of clonal propagation in response to clipping (Inula). Both these traits suggest rapid adaptation to the contrasting mowing regimes in restored in comparison to the natural donor sites. In Centaurea, we detected no differentiation, neither in-situ, nor in the common garden. Rapid evolution in two out of three species indicates that evolution in restoration may be rather common, yet not ubiquitous across species.

Plant species phenology differs between climate and land‐use scenarios and relates to plant functional traits

“…Phenological studies on the effects of land‐use type are scarce and usually link their findings to genetic differentiation and evolutionary processes that act on a larger temporal scale (Reisch & Poschlod, 2009; Völler et al., 2013, 2017). However, rapid responses of the flowering time to land use or other drivers such as climate have also been shown (Bucharova et al., 2024; Franks et al., 2007; Rauschkolb et al., 2022; Zopfi, 1993). Due to the comparably short duration of the experiment (6 years by the time of our study), we think that genetic differentiation or evolutionary processes have not yet played a prominent role in our study system, at least not for the perennial species strongly dominating our dataset.…”

“…Thus, these species did not show strong responses. Another reason for species not responding to climate and/or land‐use treatments may relate to the comparably short duration of the experiment (6 years), that makes genetic differentiation or evolutionary processes rather unlikely in our study system (not impossible though: Bucharova et al., 2024; Franks et al., 2007; Rauschkolb et al., 2022; Zopfi, 1993). Non‐responding species could also be rather controlled by photoperiod than by climate (Flynn & Wolkovich, 2018; Meng et al., 2021) or characterized by a generally lower trait plasticity (Zhang et al., 2020), but further investigations would be necessary to test this.…”

Rapid evolution of flower phenology and clonality in restored populations of multiple grassland species

“…Data are available from the Dryad Digital Repository: https://doi.org/10.5061/dryad.280gb5mx2 (Bucharova et al., 2024).…”