Key issues in Northwestern Mediterranean dry grassland restoration

• Published in: Restoration ecology Vol. 29; no. S1
• Main Authors: Buisson, Elise, De Almeida, Tania, Durbecq, Aure, Arruda, André J., Vidaller, Christel, Alignan, Jean‐François, Toma, Tiago S. P., Hess, Manon C. M., Pavon, Daniel, Isselin‐Nondedeu, Francis, Jaunatre, Renaud, Moinardeau, Cannelle, Young, Truman P., Mesléard, François, Dutoit, Thierry, Blight, Olivier, Bischoff, Armin
• Format: Journal Article
• Language: English
• Published: Malden, USA Wiley Periodicals, Inc 01.04.2021; Blackwell Publishing Ltd
• Subjects: Climate; death; Drought; Ecological effects; ecosystem engineers; Encroachment; Environmental policy; Environmental restoration; Fires; grassland restoration; Grasslands; Grazing; grazing and fire management; hay; Herbivores; humans; issues and policy; local adaptation; Mediterranean climate; Mediterranean region; Natura 2000 habitat #6220; Nutrient content; Pasture management; phenology; Plant species; Rain; Rainfall; rangeland; Rangelands; Restoration; seed bank; Seed banks; Seed dispersal; Seeding; seedling recruitment; Seedlings; Seeds; shrubs; Soil; Soil nutrients; Soils; sowing; Species; species pool; species recruitment; Transplantation; weeds; Mediterranean Area; Mediterranean region
• ISSN: 1061-2971; 1526-100X
• DOI: 10.1111/rec.13258

Dry grasslands of the Northwestern Mediterranean Basin are seminatural species‐rich ecosystems, composed of many annual species and some structuring perennial species. As these grasslands have been used as rangelands for centuries, human management (grazing; fire regimes) is one of their main ecological and evolutionary drivers, along with the Mediterranean climate. Despite EU conservation policy, damage to such grasslands still occurs and efficient ecological restoration is needed. This article reviews restoration constraints, effective techniques, and research perspectives for restoring them in the light of their ecological characteristics. Major restoration constraints specifically include (1) a poor contribution of the internal (seed bank) and external (seed rain) species pools, and (2) low establishment of some perennial species. The latter may be the result of the low seed quantity or quality of perennial species, stochastic or extended droughts, high soil nutrient content that may lead to competition (e.g. between weed and target species), inappropriate grazing management or fire regimes leading to shrub encroachment, or the death of target species seedlings in early stages of restoration. Successful restoration techniques include seeding, transplanting, hay transfer, and timely soil transfer, all of which have to be adapted to regional plant phenology and to local Mediterranean climate. They must be combined with appropriate grazing or fire management. Their success may depend on years with particular rainfall amounts or patterns or on particular target plant species. We discuss research perspectives contributing to a better understanding of seed dispersal, seedling recruitment, and soil processes and suggest the benefits of using ecosystem engineer species.