Health Regeneration

Lore & Background

Forest restoration is a specialized form of reforestation, distinct from conventional tree plantations because its primary goals are biodiversity recovery and environmental protection. The United Nations Decade on Ecosystem Restoration (2021–2030) provides the opportunity to restore hundreds of millions of hectares of degraded forests and other ecosystems. Successful restoration requires understanding the ecological characteristics of component species and how they assemble, interact and function as communities. According to FAO's The State of the World's Forests 2020, large-scale forest restoration is needed to meet the Sustainable Development Goals and prevent, halt and reverse biodiversity loss. While 61 countries have pledged to restore 170 million hectares under the Bonn Challenge, progress to date is slow. Forest restoration, when implemented appropriately, helps restore habitats and ecosystems, creates jobs and income, and is an effective nature-based solution to climate change. Moreover, according to FAO, forest and landscape restoration yields many benefits for the climate, including greenhouse gas emissions sequestration and reduction.

In Their Own Story

In a degraded patch of tropical forest, a team of restoration ecologists studies how natural regeneration works. They identify limiting factors—fire, cattle grazing, lack of seed sources—and devise methods to overcome them. They fence off the area, remove cattle, and allow light-loving pioneer species to establish. These pioneers foster recolonization by shade-tolerant climax forest tree species via natural seed dispersal from remnant forest. But because this process is slow, they also plant large-seeded, poorly dispersed climax species. They do not plant every species that once grew there—that would be infeasible—but use the framework species method to accelerate biodiversity recovery. Active restoration has been shown to accelerate carbon recovery of human-modified tropical forests by as much as 50%.

Reader's Guide

Forest restoration may include simply protecting remnant vegetation (fire prevention, cattle exclusion) or more active interventions like tree planting and direct seeding of species characteristic of the target ecosystem. Where people live in or near restoration sites, projects often include economic species among planted trees to yield subsistence or cash-generating products. Restoration is an inclusive process depending on collaboration among local communities, government officials, NGOs, scientists and funding agencies. Ecological success is measured by increased biological diversity, biomass, primary productivity, soil organic matter and water-holding capacity, as well as the return of rare and keystone species. According to FAO, restoration faces economic barriers from lack of large-scale government funding to limited resources of smallholders. Economic indices of success include the value of forest products and ecological services (e.g., watershed protection, carbon storage), which contribute to poverty reduction. Payments for ecological services (PES) and forest products can provide strong incentives for local people to implement restoration projects. Forest restoration is appropriate wherever biodiversity recovery is a main goal—such as wildlife conservation, environmental protection, eco-tourism, or supplying forest products to local communities. Degraded sites within protected areas are high priority, especially where some climax forest remains as a seed source. Many projects now operate under 'forest landscape restoration' (FLR), defined as a planned process to regain ecological integrity and enhance human well-being in deforested or degraded landscapes. FLR recognizes that restoration has social and economic functions and aims for the best compromise between conservation goals and rural community needs. A recent focal area is urban forest restoration, where both people and biodiversity benefit, though it presents unique challenges. Natural regeneration can be accelerated by weeding, fertilizing around seedlings, preventing fire, and removing cattle—this is 'assisted natural regeneration.' It is simple and cost-effective but only works on existing trees, mostly light-loving pioneers. These are not usually climax species, but they can foster recolonization by shade-tolerant climax species via natural seed dispersal. Because this is slow, planting some climax forest tree species—especially large-seeded, poorly dispersed ones—can accelerate biodiversity recovery. It is not feasible to plant all former species, and usually unnecessary if the framework species method is used. In some exceptional cases, like Alaskan boreal forests, long-term recovery from wildfires could offset carbon emitted during fires due to a change in tree species, if the trees persist and become part of resilient biomes. Forest in restoration is notably susceptible to browsing animals. Over-grazing can damage young saplings beyond recovery, decreasing biodiversity. Care must be taken to use deer fencing or, where not financially possible, to plant trees that prioritize structural growth and recovery. In large parts of the world, forest fires cause heavy losses—from provoked deforestation for crops or natural wildfires. A whole section of FLR addresses this, as net loss of ecosystem value can be high and lead to further degradation through erosion and desertification, with dire consequences for habitats and fauna. However, in some specific cases, wildfires increase biodiversity index, and restoration strategies then look for different land-use. A study finds that almost 300 million people live on tropical forest restoration opportunity land in the Global South, constituting a large share of low-income countries' populations, and argues for prioritized inclusion of local communities in restoration projects. Project Drawdown lists restoration of tropical forests as one of the most important solutions for climate change mitigation due to its extraordinary potential to sequester carbon, and recommends that local communities need a stake in what is growing. A recent FAO publication reports that Indigenous Peoples are among those facing the greatest risk to their well-being and livelihoods from climate change, and therefore must be included in restoration efforts.

Did You Know?

• Active restoration has been shown to accelerate carbon recovery of human-modified tropical forests by as much as 50%.
• 61 countries have pledged to restore 170 million hectares of degraded forest lands under the Bonn Challenge, but progress to date is slow.
• The United Nations Decade on Ecosystem Restoration (2021–2030) aims to restore hundreds of millions of hectares of degraded forests and other ecosystems.
• Almost 300 million people live on tropical forest restoration opportunity land in the Global South.
• In some Alaskan boreal forests, long-term recovery from wildfires could offset carbon emitted during the fires due to a change in tree species.