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Deforestation and forest degradation continue at alarming rates. Landowners often clear forest patches for alternative use, creating landscape mosaics of different land‐use legacies. Ecological restoration is usually monitored by aboveground processes, while belowground processes are far less studied. We addressed how the abundance and activity of nutrient improvement bacteria contribute to restoration success, considering different restoration interventions and land‐use legacies. We assessed the abundance and potential activity of N‐fixing and P‐mineralizing bacteria in the rhizosphere of 279 two‐year‐old Quercus mexicana plantlets in a disturbed oak forest in central Mexico. We analyzed the differences across landscape patches (eroded landslide, pastureland, and forest) of four common restoration interventions: passive restoration, artificial shading, topsoil translocation, and combining both treatments. Restoration interventions modified soil functioning differently across landscape patches with a significant increase of P‐mineralizing bacteria abundance and potential activity in the landslide and pastureland. In contrast, N‐fixing bacteria increased only in the landslide site where we registered the lowest organic matter content. Surprisingly, interventions that enhance bacterial activity and abundance do not necessarily improve short‐term seedling performance. We recommend considering the landscape heterogeneity to better match the restoration interventions with the prevailing degradation factor in each landscape patch. Also, combining restoration strategies does not necessarily result in synergy and may imply a useless expense of resources. Finally, monitoring soil health provides novel insights to understand restoration trajectories that remain undetected when focusing only on seedling performance. [ABSTRACT FROM AUTHOR]

The natural regeneration of forests is declining in human‐modified landscapes and overcoming ecological barriers to the seedling establishment is paramount to its restoration. This study focus on two common forest regeneration barriers: excessive sun exposure and low‐quality soils. A degraded clearing with eroded and compacted soils within a disturbed oak forest in Mexico was chosen, and 20 experimental plots in a randomized factorial block design were set up to test seedling performance in the artificial shade and in forest topsoil that was transferred from a nearby remnant forest, as well as a combination of both. We sowed 400 acorns from two oak species (Quercus eduardii and Q. viminea) and monitored the emerging seedlings for 63 months. Our results confirm different survival and growth rates between species, ontogenetic stages, and environmental micro‐conditions. The effect of artificial shade on seedling performance was positive in weathered soil but negative or neutral in transferred forest soil. Restoration interventions did not have additive benefits; seedling performance was improved by both restoration interventions applied separately though was not further enhanced when both actions were combined. Both species had different mechanisms to cope with water stress, which resulted in different photosynthetic rates under full sun. Trade‐offs resulted in different life stages that were more enhanced by different restoration strategies; survival and growth were most enhanced by applying artificial shade or transferring forest topsoil, respectively. Restoration practitioners may prioritize seedling survival in harsh conditions and growth in less severe degraded sites or apply interventions sequentially over time. [ABSTRACT FROM AUTHOR]