How the the African Forest Restoration Initiative threatens savannas and grasslands

“Increasing tree cover in open ecosystems globally represents a major threat.”

A recent paper published in Science warns that “Across Africa, vast areas of nonforest are threatened by inappropriate restoration in the form of tree planting.”

The paper, titled “Conflation of reforestation with restoration is widespread” is written by Catherine Parr (Liverpool University, Pretoria University, and Witwatersrand University), Mariska te Beest (Utrecht University, Nelson Mandela University), and Nicola Stevens (Witwatersrand University and Oxford University).

The paper focusses on restoration pledges under the African Forest Restoration Initiative (AFR100) as well as on-the-ground projects. The authors found that “tree planting is widespread across nonforest systems”.

AFR100 aims to restore 100 million hectares across Africa by 2030 through planting and natural regeneration of trees. A total of 133.6 million hectares in 35 countries has been pledged to AFR100 - one-third more than the original target.

The authors write that,

In practice, the principal restoration activities focus on increasing tree cover, whether by seedling planting, natural regeneration, agroforestry (incorporation of trees into agricultural systems), or management plantations, and therefore broadly assume that degradation can be remedied by increasing tree cover.

FAO’s forest definition

Part of the problem is the UN Food and Agriculture Organisation’s definition of forests. FAO defines a forest as an areas covered in trees with canopy cover of at least 10%.

This definition fails to differentiate between industrial tree plantations and old-growth forests, and as Carr, te Beest, and Stevens point out it can also be used “to erroneously classify open systems with trees, such as savanna, as forest”.

“At the root of the problem,” they write, “is that the grassy biomes remain fundamentally misunderstood and consequently are misclassified as forest.”

The FAO’s forest definition only considers tree cover, and fails to recognise the grass covering the ground below the scattered trees. Savannas are “structurally, functionally, and compositionally distinct from forests,” the authors write.

Restoration that increases tree cover in nonforest ecosystems “can be problematic because high tree cover can degrade them”, the authors write.

Planting trees in grassy systems increases canopy cover and reduces light with consequent structural, compositional, and functional changes to the understory; in some grassy systems, this can result in wholesale biodiversity loss, notably of shade-intolerant species associated with open habitats, as well as changes in ecosystem functioning, declines in critical ecosystem services (e.g., reduced water availability, restricted access to food and medicinal resources), and even unintended climate warming due to reduced albedo. Degradation by tree planting results in the permanent transformation of grassy systems with low likelihood, and/or extremely slow rate, of recovery.

AFR100 pledges: 52.5% target nonforest ecosystems

The authors looked at the area pledged for forest restoration in each country. They also looked at restoration projects taking place in AFR100 countries, using the Mongabay Reforestation database to determine whether savannas and other nonforest ecosystems are the target of tree planting projects.

They found that for 18 out of the 35 countries involved in AFR100, the pledged area is larger than the forest area in the country. Almost 20% of the area pledged for forest landscape restoration (25.9 million hectares) is in eight countries with little or no forest area. Another 25 million hectares is targeted for nonforest ecosystems.

A further 19.2 million hectares has been pledged in forest areas that do not need restoring.

In total, 70.1 million hectares, 52.5% of the total area pledged, is in nonforest ecosystems, mainly savannas and grasslands. “[T]his is greater than the area of France,” the authors note, “indicating that tree-based restoration in Africa could cover vast areas of nonforest habit”.

This targeting of savannas and grasslands is completely unnecessary to achieve AFR100’ targets. The authors point out that there is a total of 176.3 million hectares of degraded forest in the 35 countries signed up to AFR100.

[I]f the total committed area were focused on truly degraded forest, instead of of nonforest systems, three-quarters (75.8%) of degraded forests in AFR100 countries could be restored (see the figure) and extensive afforestation avoided.

Restoring grasslands and savanna?

AFR100 claims to support restoration of grasslands and savanna with native grasses rather than tree planting. But the authors could find only one project actively restoring grassland all other projects are focused on increasing the number of trees.

The data from on-the-ground restoration projects reveals 76% of tree planting projects are targeted at nonforest ecosystems. And 49% of agroforestry projects are aimed at nonforest ecosystems.

Even worse, nearly 60% of agroforestry projects use non-native species. This runs the risk of invasive species, such as Grevillea robusta which is a popular agroforestry tree, becoming a serious problem.

Another problem with agroforestry in grasslands is that ecosystem processes such as fire and grazing often conflict with agroforestry. Yet these processes are critical to the functioning and the biodiversity of tropical grasslands.

The authors write that,

Most projects have as their aim improving livelihoods and restoring degraded and/or deforested areas, but critical information on what aspects of degradation are being restored, as well as monitoring and performance indicators, are seldom openly available, and finding information on these aspects of projects is challenging.

These projects have received more than US$1 billion in development finance, and US$148 million from the private sector. Funding comes from the German government, IUCN, the UN, the FAO, the Global Environmental Facility, and NGOs such as The Nature Conservancy, as well as Bezos Earth Fund and Meta.

Andrew Steer, President and CEO of the Bezos Earth Fund says that,

“Africa’s restoration movement is at a positive tipping point. We are proud to stand with other philanthropic partners in support of locally led restoration. With the right capital, capacity, and connections, these local leaders can change the trajectory of global climate and biodiversity crises.”

Which all sounds great, but the reality is very different. As the authors of the Science paper note, “it is essential that the projects are transparent and accountable, or they will be at risk of greenwashing”.

Carr, te Beest, and Stevens conclude that,

Increasing tree cover in open ecosystems globally represents a major threat, not only for the ecosystems themselves but ultimately for society as a whole, and tree-planting actions will exacerbate already problematic woody encroachment. We urge a paradigm shift away from the structural focus on trees to include the distinctive and important characteristics and ecology of grassy, nonforest systems. . . .

Ultimately, the right trees and the right number need to be planted in the right place. But, until the definition of forest is revised, there will always be the double jeopardy of afforestation of ancient grasslands and deforestation of virgin forest. We must act to avoid a situation where we cannot see the savanna for the trees, and these precious grassy systems are lost irrevocably.

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