Using priority effects for grassland restoration: Sequential sowing can promote subordinate species

Abstract

AimsThe influence of priority effects on plant community succession is increasingly discussed in community ecology. However, most grassland restoration approaches involving seed addition transfer all target species at the same time. Our objective was to tackle the question: does the order of arrival influence the establishment of restored communities?LocationLa‐Bâtie‐Neuve, Southern Alps, France.MethodsWe applied sequential sowing using two groups, one set of dominant species and one set of subordinate species, each comprising three different perennial plant species. We tested four sowing treatments: control (without any sowing), two sequential sowing treatments (dominants first or subordinates first) and synchronous sowing. We analysed plant cover each year for three years after sowing and calculated priority and earliness indices (the third year) for each group and each sown species.ResultsManipulating the order of arrival shaped community composition and trajectories. Some species of both groups were positively affected by being sown first compared to being sown synchronously. However, dominant and subordinate groups differed in their earliness index, showing a significant benefit for subordinates to be sown first. The subordinate species Onobrychis viciifolia and Plantago lanceolata established only when they were sown first, while Festuca cinerea showed greater establishment when sown first and simultaneously, compared to late sowing. The dominant Anthyllis vulneraria was not affected by date or type of sowing. However, the cover of the most dominant Bromopsis erecta was lower when being sown second, allowing a control of its dominance by delayed sowing.ConclusionThe strength of priority effects differs between species, which may depend on niche characteristics or microenvironment, influencing (negatively or positively) the establishment of late‐arriving species and affecting their competitive abilities. Our study provides evidence that plant community assembly was influenced by the order of arrival, but demonstrated a strong species‐specific response to priority effects.

Reflecting on two and a half decades of restoration ecology in Applied Vegetation Science (1998–2023)

“…Each year, the Chief Editors of Applied Vegetation Science select an article for the Editors' Award, also considering recommendations from Co-ordinating Editors. The award for 2023 goes to Aure Durbecq for the article "Using priority effects for grassland restoration: Sequential sowing can promote subordinate species" (Durbecq et al, 2023). This article explores the sequential sowing of dominant and subordinate plant species to answer the question of whether the order of arrival influences the establishment of restored communities.…”

“…The 2023 articles also continued to explore the reintroduction of plant species to degraded sites, highlighting the enduring challenges associated with restoring various species. Notably, there was a shift towards more active techniques; for example, sequential sowing to facilitate the establishment of subordinate species (Durbecq et al, 2023).…”