Overcoming biotic homogenization in ecological restoration

• Published in: Trends in ecology & evolution (Amsterdam) 2022-09, Vol.37 (9), p.777-788
• Main Authors: Holl, Karen D., Luong, Justin C., Brancalion, Pedro H.S.
• Format: Article
• Language: English
• Subjects: diversity conservation; gamma-diversity; habitat heterogeneity; reintroduction; rewilding
• ISSN: 0169-5347; 1872-8383
• DOI: 10.1016/j.tree.2022.05.002

Extensive evidence shows that regional (gamma) diversity is often lower across restored landscapes than in reference landscapes, in part due to common restoration practices that favor widespread species through selection of easily-grown species with high survival and propagation practices that reduce genetic diversity. We discuss approaches to counteract biotic homogenization, such as reintroducing species that are adapted to localized habitat conditions and are unlikely to colonize naturally; periodically reintroducing propagules from remnant populations to increase genetic diversity; and reintroducing higher trophic level fauna to restore interaction networks and processes that promote habitat heterogeneity. Several policy changes would also increase regional diversity; these include regional coordination amongst restoration groups, financial incentives to organizations producing conservation-valued species, and experimental designations for rare species introductions. Anthropogenic activities are leading to biotic homogenization.Common ecological restoration practices often contribute, rather than counteract biotic homogenization at the species, functional, and phylogenetic levels.It is important to think critically about how to integrate individual restoration projects to most effectively conserve regional biodiversity.We offer several recommendations to improve restoration practices and policies to increase gamma-diversity in order to maintain ecosystem resilience in a changing world.