Restoring the world’s forests, peatlands, grasslands and coastal wetlands is one of the most promising approaches for combatting the climate crisis and reversing biodiversity loss. If designed well and implemented appropriately, these efforts can also deliver multiple sustainable development benefits.
Restoration and protection must go hand in hand to conserve ecosystems
However, restoration cannot cancel out the impacts of ecosystem loss. For example, it can take decades or longer to fully recover species diversity, ecosystem structure and ecological functions, all of which impact carbon cycling and greenhouse gas (GHG) fluxes. Restoration efforts should therefore complement — but not replace — measures aimed at protecting forests, peatlands, coastal wetlands and grasslands.
Reforestation and other forms of ecosystem restoration generate substantial climate benefits
Reforestation — particularly natural regeneration and assisted natural regeneration — can deliver substantial near-term carbon removals at relatively low costs when compared to more nascent technological approaches like direct air capture. At the same time, swiftly restoring ecosystems that store carbon primarily belowground (including peatlands, grasslands and coastal wetlands) can not only reduce emissions from degrading soils but also enhance carbon sequestration and storage. Together, these measures can contribute nearly one-third of the mitigation needed from terrestrial ecosystems globally in 1.5-degree-C pathways.
Restoring degraded agricultural lands — for instance, by integrating trees in croplands and pasturelands or improving grazing practices across intensively managed grasslands — can generate additional mitigation benefits while enhancing productivity. When implemented alongside ecosystem restoration, these interventions across food and agriculture systems can help spur more durable change.
The importance of adhering to ecological restoration principles to reverse biodiversity loss
However, narrowly focusing on restoration on maximizing carbon removals can backfire. By one estimate, commercial-scale, monoculture plantations of nonnative tree species account for nearly half of the Bonn Challenge commitments to restore forest landscapes. While such initiatives may achieve impressive carbon sequestration rates in the near term, these monocultures lack the functional diversity underpinning ecological resilience and are often more vulnerable to climate impacts and other disturbances that ultimately limit long-term carbon sequestration and storage.
In some instances, these projects may also harm local biodiversity by displacing naturally non-forested ecosystems altogether. For example, scientists have raised concerns about tree-planting efforts occurring across grasslands. But by adhering to broader ecological restoration principles — including focusing on reestablishing a diversity of native species, recovering ecosystem structures and functions, maximizing ecological connectivity, prioritizing natural or assisted natural regeneration wherever possible, and delivering multiple benefits across entire landscapes — restoration efforts can not only avoid unintended negative consequences but also help recover terrestrial biodiversity.
Global efforts to accelerate ecosystem restoration are falling short
Yet globally, a persistent gap remains between restoration’s substantial potential to help combat these crises and current efforts to realize these benefits in practice. The most recent data on gross tree cover gains indicates that progress made in reforesting 100 million hectares by 2030 is well off track, such that pace of collective efforts needs to double to get on track. Current rates of mangrove restoration are also well off track and need to accelerate more than 10-fold by the end of this decade. Even where data is insufficient to assess global action, available evidence suggests that most restoration initiatives are likely small-scale or occurring too slowly, underscoring the urgent need for a step change in action.
Join us on October 27 for the launch of new data and insights on the state of the world's forest and land.
