Largest afforestation project

The world's largest afforestation project is the "Green Great Wall Initiative". A 7,775-km-long (4,831-mi) and 15-km-wide (9-mi) belt of "regreened" land is being created across Sub-Saharan Africa from Senegal in the west to Djibouti in the east - a region known as the Sahel. The objective is to combat the encroaching threat of desertification, make the land once again more viable for cultivation and to help future-proof Sahelian communities with improved water access, greater food security and the adoption of more sustainable energy sources such as solar power. Launched in 2007, the ambition is to restore 100 million hectares (247.1 million acres) of degraded land by 2030. The project is being co-ordinated by the African Union Commission and Pan-African Agency of the Great Green Wall, with support from the UN Convention to Combat Desertification (UNCCD), the World Bank and the European Union.

A decade in, around 15% of the huge project is now underway. Key results to date include 11.4 million trees being planted in Senegal (with 25,000 ha/62,000 acres of land restored), 16.6 million plants and seedlings planted in Burkina Faso, 15 million ha (37 million acres) of degraded land restored in Ethiopia and 5 million ha (12.4 million acres) in Nigeria.

While there have been many successes, the project has faced criticism for lagging far behind its target deadline of 2030; as of 2020, a status report indicated only 4% of the proposed 100 million ha had been reforested. The scope of the project has also had to adapt from an initiative originally focused on planting trees to one that is more flexible from region to region which utliizes local knowledge and techniques to improve land fertility, as tree-planting is not always the most effective solution.

Another afforestation project, also called the "Great Green Wall", has been taking place in north-west China on the edge of the Gobi Desert since 1978. By 2050, its aim is to have created a 4,480-km (2,783-mi) belt of forest with a total coverage of 35.6 million ha (87.9 million acres).