Does plantation forestry restore biodiversity or create green deserts? A synthesis of the effects of land-use transitions on plant species richness

TLDR

Plantations are established for wood production, soil and water conservation, and carbon sequestration, yet their impact on biodiversity is poorly understood and debated as to whether they are green deserts or valuable habitats. This study synthesizes peer‑reviewed articles that provide quantitative data on plant species richness in plantations and their paired land uses. The synthesis compiles and compares these quantitative data across studies to assess how plantation establishment affects plant species richness relative to representative pre‑plantation land covers. Results indicate that plantations most benefit biodiversity when established on degraded lands and using indigenous tree species, whereas replacing natural ecosystems or planting exotic species reduces biodiversity, offering guidance for afforestation and reforestation aimed at carbon sequestration.

Abstract

Plantations are established for a variety of reasons including wood production, soil and water conservation, and more recently, carbon sequestration. The effect of this growing land-use change on biodiversity, however, is poorly understood and considerable debate exists as to whether plantations are 'green deserts' or valuable habitat for indigenous flora and fauna. This paper synthesizes peer-reviewed articles that provide quantitative data on plant species richness in plantations and paired land uses, most often representative of pre-plantation land cover. The results of this synthesis suggest that the value of plantations for biodiversity varies considerably depending on whether the original land cover is grassland, shrubland, primary forest, secondary forest, or degraded or exotic pasture, and whether native or exotic tree species are planted. The results of this study suggest that plantations are most likely to contribute to biodiversity when established on degraded lands rather than replacing natural ecosystems, such as forests, grasslands, and shrublands, and when indigenous tree species are used rather than exotic species. These findings can help guide afforestation and reforestation programs, including those aimed at increasing terrestrial carbon sequestration.