Scaling the wall

Daniel McGahey and Jonathan Davies discuss boosting private investment in the Great Green Wall, a landscape restoration project spanning the African Sahel region

The Great Green Wall is an African-led initiative that aims to combat desertification, reduce poverty and address climate change by restoring and managing a belt of land across the Sahel, from Senegal to Djibouti. It was originally envisioned 
as the restoration of an 8,000km-long, 15km-wide band of trees, in defence against an advancing Sahara. 

However, environmental changes in dryland ecological systems are nuanced, and notions of a desertification crisis in the region have long been critiqued by scientists. The project has thus evolved, and now plans to create a 780m-hectare mosaic of restored, healthy, productive and resilient landscapes across the Sahel – principally through targeted investments 
in land restoration, natural regeneration and sustainable land management. The land’s restored ecological function could positively impact the livelihoods of around 232 million people. 

The initiative has secured political will and solidarity among the 21 African countries now involved, as well as financial resources from the international community – including more than US$4bn of pledged donor funding. However, between 2007 and 2017, only 15% of the original target of 100m hectares was restored, mainly through the planting of 12m trees in Senegal. There is a growing sense that to meet the initiative’s ambitions, significant scale-up of financing and action is required. The private sector’s role, as a source of investment and as a key partner with influence on the ground, will be critical. 

Finance and technical assistance 

There is no dedicated national or region-wide public-private investment funding platform for the Great Green Wall, which means it is reliant on public financing and the willingness of local farmers. This reflects the global land restoration market context: of the estimated US$5-10bn currently invested in forest and landscape restoration each year, 90% still comes from public sources. There is space for optimism, however, as a growing number of agroforestry investment funds are currently seeking investable projects and can provide much-needed technical support to project developers. Examples such as the Land Degradation Neutrality Fund, established in 2016 by the UN Convention to Combat Desertification’s Global Mechanism, 
or the Moringa Fund, established in 2010, show there is no shortage of private capital.

Most Great Green Wall countries lack sufficient objective evidence on the scale of land degradation. This makes it tricky 
to target actions and monitor progress. The Sahel’s land cover consists of a transition between moist Guinea savannah woodlands to the south and decreasing tree cover to the north, where the landscape transitions through grassland, thorny shrubland and desert ecosystem. Businesses need to know where they can invest in tree cover restoration, where agribusinesses can be incentivised to adopt sustainable land management practices, and where sustainable livestock production can be promoted to restore degraded grasslands. 

Detailed satellite mapping, using measurements of net primary productivity, is needed in grasslands and savannahs – but is rarely conducted. This means that grassland degradation through overgrazing-induced bush encroachment and invasive species is poorly monitored. In 2016, the UN Food and Agriculture Organization published analysis suggesting that 166m hectares of this region has inadequate tree cover, but did not estimate the ecosystem restoration potential for grasslands, which cover 243m hectares of the Great Green Wall area.  

Underlying values

Public agencies aiming to stimulate private sector engagement must understand the ecosystem service values that are at stake, and the value they present to the market. Much of the land targeted for restoration is productive dryland, primarily used for agriculture. Restoration is possible through sustainable land management, including practices such as agroforestry, conservation agriculture and pasture management. 

Restored agricultural dryland can provide a number of benefits in addition to enhanced food production: it can improve green water storage, reduce drought risks, improve groundwater supplies, enhance soil carbon stocks, and contribute to climate change mitigation and biodiversity conservation. These benefits include off-farm values for which regional or international ecosystem service markets may or may not be available. 

Governments need a better understanding of the role that private sector investment will play. This understanding is required on a number of levels, from the daily decision-making of farmers around the risks associated with changing production systems, to the policies and perverse incentives that limit investment in sustainable practices or ecosystem service products. 

Restoring agricultural drylands within the Great Green Wall will create marketable products for farmers, including gums, resins, fruits and nuts – all of which have established international value chains. Ecosystem service benefits such as carbon sequestration create opportunities to attract investors that are interested in certified voluntary carbon offsets. 

Successful examples exist, and partnerships between NGOs, aid agencies, multinational companies and communities are common. In Chad, for example, an acacia gum project led by NGO SOS Sahel involved a public-private sector financing coalition between the French Development Agency, Swiss flavour company Firmenich, global agrifood business Danone and French natural ingredient retailer Nexira. The partnership improved the livelihoods of some 60,000 people involved in gum production and the preservation of acacia gum forests. 

An enabling policy framework 

Strong international value chains can be linked to natural gum, resin and nut products from restored dryland agroforestry landscapes. These value chains help to generate revenues that de-risk investments. The region has several agroforestry restoration traditions, such as farmer-assisted natural regeneration, that provide a scientific evidence base facilitating carbon certification. However, capitalising on these enabling factors and scaling up positive examples will require a mindset change in a region where agricultural development policy tends to favour capital-intensive commercial farming. 

There needs to be reform of public policies to remove negative regulatory incentives such as subsidies or taxes. One example would be to provide farmers with secure tenure so that they can invest in and manage trees and forest products. 

Many such incentives could be reformed, and blended public-private financing mechanisms used, to enable the wider adoption and scale-up of land restoration across the Great Green Wall. 


Further reading

Find out more about the Great Green Wall project in Building Africa’s Great Green Wall: Restoring Degraded Drylands for Stronger and More Resilient Communities, at

Read the UN report Sustainable Financing for Forest and Landscape Restoration: Opportunities, Challenges and the 
Way Forward

Dr Daniel McGahey, MIEMA CEnv, is an environmental consultant with Earth Systems Ltd and works on international environmental management and assessment projects across Africa and south-east Asia. 

Dr Jonathan Davies is global drylands coordinator and senior agriculture advisor at the International Union for Conservation of Nature.

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