Spanning the continent of Africa, the "Great Green Wall" project has restored over 7.7 million hectares of land after 17 years.
Over the past few decades, deforestation, agricultural expansion, and drought have contributed to desertification across much of Africa. Fertile topsoil becomes barren and less productive. More than a dozen African nations are combating desertification with an ambitious project to plant trees and vegetation over 100 million hectares of land, an area more than 2.3 times the size of California. The 17-year-old Great Green Wall (GGW) aims to create 10 million jobs and reduce 250 million tons of carbon by 2030, at an estimated cost of $36-49 billion, according to Business Insider.
Re-greening the Sahel
Nations from Senegal to Djibouti are attempting to regreen the semi-arid Sahel, a strip of land stretching from the Atlantic Ocean to the Red Sea. West African forests once covered over 50,000 square miles. Since 1975, deforestation, largely for agricultural expansion, has reduced the region's forests by approximately 32,000 square miles, according to the U.S. Geological Survey. In addition to depleting soil, desertification makes land more susceptible to wind erosion and reduces its ability to retain moisture. It also leads to a loss of biodiversity in plant and animal life. Together, these factors make it harder for humans to survive.
The African Union officially launched the initiative in 2007. The GGW initially included 11 countries: Burkina Faso, Chad, Djibouti, Eritrea, Ethiopia, Mali, Mauritania, Niger, Nigeria, Senegal, and Sudan. Several more countries joined in the years that followed. The project initially aimed to plant trees across 4,000 miles of the Sahel. Trees can help slow soil erosion, absorb carbon dioxide, and promote biodiversity by providing food and shelter for animals.
Critics and Challenges
However, critics have pointed to shortcomings, and the project has faced several obstacles. A major issue with tree-planting initiatives is the trees themselves. Some saplings fail to thrive or die. They are often planted in remote areas, making maintenance difficult. Rising temperatures and low rainfall have also contributed to the problem. Some communities have argued that governments have failed to adequately involve local Indigenous people in the project. Governments in several countries have forcibly relocated many people from their homes in forest areas and conservation zones.
The GGW's success has also been difficult to track in some areas. Independent experts have struggled to verify some government data. By 2020, the project was only 4% complete. In 2021, world leaders pledged $19 billion to help monitor and boost the project's progress.
Shifting Focus
The GGW's focus has since shifted toward incorporating traditional farming and water management techniques. Prior to the GGW initiative, locals in parts of Niger and Burkina Faso had begun using a technique known as farmer-managed natural regeneration. Instead of planting new trees, farmers in south-central Niger encouraged the growth of existing shrubs and large trees. The effort helped to regreen five million acres and establish two million trees. In Burkina Faso, farmers drew on traditional knowledge to adapt to droughts in the 1970s and 1980s. They dug deep pits called zai and installed stone barriers to help collect and conserve moisture.
Recent Successes
Since the GGW's inception, several countries have seen success with smaller, farmer-led projects. In Senegal, farmers began planting zai gardens during COVID-19 lockdowns. Known as "Tolou Keur" in Wolof, the crescent-shaped pits capture and direct water to crops. While not all Tolou Keur survive, many are thriving, with farmers cultivating everything from sorghum to hibiscus. The crescent pits are quick to build, take up minimal space, and require only around 10 people to maintain.
Drones and satellites have recently begun to provide detailed information about the regenerating land, using AI to identify individual plant species. Several tech startups and organizations, such as the UN's Food and Agriculture Organization (FAO), are partnering to help communities in the Sahel map and monitor populations of baobab trees, which help reduce soil erosion. Ethiopia, Niger, and Senegal have all made progress in regreening their land. In addition to the zai gardens, Senegal has planted 50,000 acres of trees. As of 2023, the United Nations Development Program reported that the GGW project was 18% complete, restoring over 7.7 million hectares of land and creating 350,000 jobs.
Summary
The "Great Green Wall" project is a major undertaking to combat desertification and its devastating effects across Africa. While the project has faced challenges, recent progress suggests that it is having a positive impact. By combining traditional knowledge with modern technology, communities are regreening the Sahel and improving the lives of people in the region.