Climatic and socioeconomic constraints to global tree restoration potential

Tree restoration is central to increasing terrestrial carbon storage and biodiversity. However, the extent to which the restoration potential for global tree cover can be released remains uncertain, because restoration efforts may involve trade-offs with other essential ecosystem services. Here we estimated an area of 1.3 billion hectares of potential tree cover restoration globally, relative to the tree cover existing in intact forests. Unlocking this potential restoration, however, is constrained by effects of climatic factors such as droughts and anthropogenic pressures associated with growing demand for socioeconomic benefits of forest resources. We project that the potential restoration of tree cover subject to climate extremes under the highest emission scenario of global warming, will increase by approximately 100% globally by 2100. This is likely to be the result of reduced potential realized tree cover and/or increasingly disturbed future forest areas. Our results highlight the influence of both climatic and socioeconomic constraints on releasing the global potential for tree cover restoration, which should be reconciled to pursue realistic goals of restoration.