Commanding the Sahara to retreat
Can Africa's Great Green Wall save the Sahel from desertification?
The blueprint for the Great Green Wall is nothing if not ambitious. Quite Canute-like, it would seem.
The aim is to plant a forest of trees about 15km wide, snaking some 7 775km from Senegal on the Atlantic to Djibouti on the Red Sea – crossing another nine Sahelian states on the way – to halt the southward march of the Sahara into the Sahel. This elongated forest would cover about 11 662 500 hectares.
The idea was originally conceived by Nigerian President Olusegun Obasanjo in 2005 and enthusiastically embraced by Senegalese President Abdoulaye Wade. In 2007, the African Union Commission (AUC) took it up as the Great Green Wall for the Sahara and Sahel Initiative (GGWSSI). Obasanjo seems to have borrowed the idea from China, yet the Chinese precedent is not entirely encouraging. Its bricks and mortar equivalent failed to keep out the Mongolian hordes from the north in the 13th century. And China’s Great Green Wall – launched in 1978 with the aim of creating a forest of trees 4 500km long – has also not stopped the southward drift of the Gobi and other deserts, despite the planting of about 70 billion trees to date.
The aim is to plant a forest of trees 15km wide, snaking from Senegal to Djibouti
In a 2012 paper published by the Comité Scientifique Français de la Désertification, a group of 13 French desertification scientists suggested that the notion of Africa’s Great Green Wall, at least in its original form, is based on several basic misconceptions. The first was that ‘the desert is a disease… that spreads into surrounding areas.’ In reality, the Sahara ‘is actually a healthy and precious ecosystem,’ they said.
The second misconception was that ‘the Sahel is being invaded by a sand sea.’ Though the Sahara’s sands do move around, such movements are local and manageable – and they are not always southwards, they said. ‘This is not a continent-wide movement trend that should be halted like an invader.’ The desertification of the Sahel is not caused by the invasion of sand from the Sahara. Instead it is the result land degradation caused by low rainfall, population concentration and poor agricultural practices, mainly over-exploitation.
The third misconception was that ‘a great forest wall could be planted in uninhabited or sparsely inhabited regions.’ Instead, the GGW would have to ‘pass through inhabited regions where agriculture and livestock farming are already fully developed,’ they said. Local inhabitants would have to be involved in the effort to combat desertification by tree planting. So, no unbroken wall of trees from west to east, but only in areas already inhabited where, indeed, there would be people present to plant and tend them.
But the GGW should be about much more than just planting trees, they wrote. It should also include integrated development of economically useful drought-tolerant plant species, building water-retention ponds, establishing agricultural production systems and other income-generating activities, as well as basic social infrastructures.
That ‘the desert is a disease’ is a misconception: the Sahara is a precious ecosystem
Key to this approach would be to preserve and encourage the growth and regeneration of local vegetation, rather than planting new trees. Decentralisation – mobilising local populations by giving them incentives to participate, for instance by planting economically beneficial plants – was also important.
The scientists also put great stress on the importance of ensuring proper socio-economic structures were in place to motivate local people to participate and avoid conflicts over competition for the resources produced. Overall their recommendations were ‘geared towards the integration of tree-planting and regeneration in a global sustainable land management framework.’ In other words, the GGW should be about much more than a great green wall.
Gray Tappan, a geographer with the United States Geological Survey, is even more emphatic that planting trees is not the way to go. ‘I have not seen any significant physical changes or improvements related to GGW activities,’ he told ISS Today.
‘We continue to map and monitor land cover across the Sahel using high-resolution imagery, and field visits… we still don’t see evidence of increased tree cover or other practices along the general belt that the GGW has targeted for intervention.’ By contrast, he says, there is another major environmental success story that has already happened and continues to spread across the Sahel. ‘This is the re-greening of much of southern Niger, and parts of Burkina and Mali. It is also known as farmer-managed natural regeneration. Just in Niger alone, some five million hectares of farmland have much more tree cover today than 20 or 30 years ago.
‘One of the keys to this success is that the trees were not planted. Planting trees in the Sahel is risky and often ends in failure. So it’s not about planting trees – it’s about farmers encouraging, protecting and managing the natural regeneration of native trees that sprout spontaneously in their fields – with a goal of greatly increasing on-farm tree cover.
Socio-economic structures are needed to motivate local people to participate
‘The benefits are enormous – from boosting crops and yields, to providing fruit, fibre and firewood, to on-farm biodiversity with entirely native Sahelian species, to protecting the soil from erosion, and more. It’s all about encouraging natural regeneration on cropland – of many native species. We often say that Niger already has its great green wall.’
Dr Elvis Paul Tangem, the coordinator of the AU’s GGWSSI initiative, insists, however, that about 15% of the actual ‘wall of trees’ has already been planted. ‘Senegal has reclaimed more than four million hectares of land along the Great Green Wall,’ Tangem told Public Radio International. ‘They have planted more than 27 000 hectares of indigenous trees that don’t need watering. Many animals that had disappeared from those regions are reappearing – animals like antelopes, hares and birds that for the past 50 years, nobody saw.’
Nonetheless, he also acknowledges that the concept has been considerably broadened to embrace a ‘mosaic’ of activities aimed at combating land degradation and desertification in the Sahel, and not just tree planting. ‘The initiative is being implemented in circum-Sahara countries, targeting communities most affected by land degradation and the advancement of the Sahara,’ he told ISS Today.
‘The initiative is a mosaic of activities; sustainable land management approaches which include agroforestry, smart agriculture, land restoration, policy and political engagements and advocacy… A multitude of projects are going on at regional and national levels, with over 20 countries, and a lot is being done within the framework of the programme. There are more than 30 partners involved under the leadership of the AU.’
The partners include the World Bank, the United Nation’s Global Environment Fund, the African Development Bank and the French government. The GGW was given a major boost during a summit of Sahel leaders and international partners at the Conference of Parties (COP) 21 climate summit in Paris in December, where it was integrated into the global strategy for combating climate change.
Planting trees in the Sahel is risky and often ends in failure
Host President François Hollande promised to step up support; and a total of some US$4 billion was pledged. And the GGWSSI held its first conference in Dakar earlier this month, where environment ministers of Sahel countries and partners assessed its progress and mapped out its future.
These included plans to tap into the potentially immense Green Climate Fund, which has been created in the COP process to direct vast resources from industrialised nations to developing nations – to help them mitigate and adapt to climate change.
The Dakar conference also launched a campaign to market the GGW to the world, stressing that it is ‘not just a tree-planting programme but an integrated programme of development.’ To emphasise this point, Tangem notes there are proposals to extend the initiative to Southern Africa, along the Namib and Kalahari deserts. So it seems the proponents and opponents of the GGW may partly be speaking at cross purposes. The more the concept is extended to embrace activities like the managed natural regeneration that Tappan describes, the more likely it is to succeed.
Tangem noted that one of the major decisions of the Dakar conference was the need to better monitor and assess the progress of the GGW. Measuring the progress of a forest of trees advancing across the African continent is relatively straightforward. Quantifying success in combating land degradation and desertification is rather more complex.
In a way, the Great Green Wall has become another part of the much greater issue of African development – losing some of its romance along the way but presumably gaining greater relevance.
Peter Fabricius, ISS Consultant
