Global deforestation and forest degradation threaten the sustainability of natural and human systems. Forest landscape restoration, through active approaches such as plantations, woodlots, boundary planting, and agroforestry, and passive approaches like exclosures, presents an opportunity to mitigate adverse effects, enhance ecosystem service recovery, and associated benefits for livelihoods. Here, using different spatial scales, we compare the contribution of both approaches to the recovery of plant diversity in southern Ethiopia. Using forest inventory data (891 plots) from multi‐aged stands, we estimated and compared alpha (α), beta (β), and gamma (γ) diversity in regeneration and tree layers between the approaches. We observed increasing α‐diversity in the order grazing lands‐active‐passive‐forest sites. β‐Diversity revealed similarity between passively restored sites and natural forests. γ‐Diversity was higher in active restoration for the regeneration layer, but passive restoration had higher γ‐diversity in the tree layer. For both approaches, γ‐diversity was consistently highest in intermediate‐aged stands (10–20 years). Results highlight the potential of active restoration strategies to facilitate vegetation recovery in human‐dominated landscapes, especially when management allows natural regeneration, while stand age variation may be associated with disturbance intensities for both approaches. Our results support a paradigm shift toward implementation of a mixture of these approaches in the landscapes to meet increasing human demands while restoring important ecosystem services like biodiversity. We recommend enhancing species diversity on restored sites to improve performance and ecosystem service recovery. On actively restored sites, we recommend protecting regenerated species; on passively restored sites, enrichment planting, increased protection, and sustainable utilization.
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