In an increasingly variable climate, land degradation poses one of the biggest threats to the future of subsistence farmers around the world. For 11 African nations, one solution to reclaiming dry, infertile land is to plant a wall of trees spanning the entire width of the continent. Although an ambitious and positive initiative, success has been limited 16 years after its inception. However, in every challenge is a lesson learned.

Last year as I stood in the dry August heat, a struggling Zimbabwean smallholder farmer, reflecting on the year’s disappointing harvest and rubbing a handful of dusty red soil between his fingers, warned me of the increasing impact of land degradation on his community’s future. “We need to reclaim the land”, he said. In that moment, I realised his livelihood, and that of the 1.5 billion other subsistence farmers, depends almost entirely on the health of their soil. Specifically, it’s ability to retain moisture, store nutrients and remain consolidated in strong wind and heavy rain. With similar scenarios reflected across sub-Saharan Africa, reclaiming land, lost to climate change and damaging land management techniques, is becoming increasingly important in creating a more sustainable future for an African population set to reach 9.8 billion by 2050.

A Great Green Wall: Success at a Localised Level

The answer to land degradation for 11 countries in the Sahel, the semi-arid region of north-west Africa, is straightforward, but by no means easy. The goal is to plant a green belt of trees 8,000km long and 15km wide from Senegal to Djibouti, bring life back to the soil and create a better future for those living off the land. Known as the Great Green Wall, this ambitious initiative has been receiving increased attention worldwide since it began in 2001, and is proving to be an important learning curve for the African Union and its environmental projects.

With the expanding Sahara Desert encroaching on its neighbours and with food and water security increasingly being threatened, the Sahel is highly vulnerable to the effects of climate change and land degradation. In response, the Great Green Wall aims to use trees to reduce wind speeds, stabilise soil, increase soil humidity and water storage, sequester up to 250 million tons of carbon and moderate temperatures. At its completion, it will be “the largest living structure on Earth and a new Wonder of the World.” Creating economic opportunities in one of the poorest parts of the world, the project acts as an example of how sustainable environmental protection can be integrated with societal well-being. So far, the biggest impact has been felt in Senegal where 11 million trees have been planted. Local communities in the country are already beginning to feel the positive impacts of the programme; reduced soil erosion, better shading resulting in increased humidity and reduced need for watering, the creation of compost and mulch from fallen tree leaves and improved retention of underground water.

Improving the Wall: Community Inclusion

Despite success at a localised level, limited political influence, coordination and funding have inhibited the project’s overall success. This project has become a learning opportunity for the people of the region. With international involvement, local communities have been marginalized from important decision-making at a challenging time when they have to adapt their traditional agricultural lifestyles to tree monocultures. Without the inclusion and contribution of affected communities, assessing the successes and limitations of the project is difficult and does little in the way of empowering the people at the grassroots level. For the project to be successful, the link between participating government bodies, local communities, scientists and funders needs to be strengthened. Although Senegal has made significant advances, other participating nations have struggled to fulfil the aims of the project. Additionally, planting trees in uninhabited areas of the region has proved a difficult geographical barrier to surmount.

Improving the Wall: The Importance of Plant Species Choice

Furthermore, increased interest in the project at a research level means there is a better understanding of how to overcome barriers to adaptation and to rethink the type of plants used in developing the wall. A study on the effectiveness of the wall argues that the Acacia species currently being planted are slow growing and commonly cut down for cooking fuel, undermining the long-term sustainability of the project. As early colonizers, shrubs reach maturity at faster rates, thereby proving more effective in keeping pace with climate change projections. This would help address the slow moving pace of the project, one of its major criticisms. Furthermore, shrubs are more resilient in areas of lower precipitation than woody tree species, ideal for the Sahel. As a knock-on effect, the faster growth rates would result in greater support from local communities, particularly if the chosen shrub species are fruit bearing and have the potential for honey production, providing a secondary means of income and the overall economic momentum to keep the project going long-term.

Looking to the Future

It is clear that while there is room for improvement, the project has become a trailblazer, elevating environmentally conscious land management techniques on the agendas of negatively affected nations in the Sahel and paving the way for future projects across the African continent. The lessons being learned from the Great Green Wall mean there is potential for similar projects to be spear-headed in Southern and Eastern Africa and has set an example for these regions to prioritise environmental solutions to land degradation. Although only one of many possible solutions, the Great Green Wall is a symbol of hope of a better life for people living in the most vulnerable climatic regions of the world. For me, personally, it’s a symbol of hope for the struggling Zimbabwean farmer I met over a year ago. With the right governmental wherewithal, scientific research and community inclusion, people like him, no matter where in the world, can find protection in the simple act of planting a tree, a shrub or a flower.

Keen on planting trees and getting active about the future? Come to our Eden Festival of Action to help us regreen the Garden Route.