Can a 4,000-mile wall of trees stop Sahara Desert's drift?

•A version of this post ran on the blog, Africa in Transition. The views expressed are the author's own.

In February 2011, an international summit in Bonn, Germany officially approved the building of a pan-African Great Green Wall (GGW) in support of the United Nations Convention to Combat Desertification (UNCCD). The initiative plans to strategically plant swaths of trees roughly nine miles wide and over 4,000 miles long.

The central idea is for this belt of forest to serve as a barrier against desert winds and thus revitalize soil to protect against land degradation. It will stretch across Africa, passing through eleven  countries – Burkina Faso, Chad, Djibouti, Eritrea, Ethiopia, Mali, Mauritania, Niger, Nigeria, Senegal, and Sudan. They have all enacted, or plan to enact, the first stages of the program.

The GGW initiative, originally envisioned by African leaders in the 1980s and 1990s, is a global response to the encroachment of the Sahara Desert into the savannas and farmlands of sub-Saharan Africa. Desertification, which now affects 40 percent of Africa, has been further exacerbated by climate change in recent decades.

Many of the continent’s most vulnerable communities living in threatened areas rely on healthy ecosystems to support livelihoods dependent on agriculture, livestock, and fisheries. They now find their livelihoods endangered. The World Food Program has warned that some ten million people risk starvation due to desertification in West Africa’s Sahel alone. Such problems are further compounded by poorly managed land and water resources.

Desertification also increases civil conflict among populations vying for arable land. Nomadic groups are constantly at odds with sedentary farmers, who often take up arms to prevent unwanted grazing. Nowhere is this better illustrated than in Nigeria’s Middle Belt – Fulani herdsmen and Berom farmers have descended into an unprecedented spiral of sectarian violence over increasingly scarce land. In fact, the Nigeria Security Tracker estimates that sectarian violence results in more deaths than the northern insurgency group known as Boko Haram.

There are initial signs of success in the GGW initiative. In Senegal, rural villagers in Widou Thiengoli have reported better harvests and more vitamin-enriched diets due to increased vegetable and fruit production.

This is not the first time that such an initiative has been undertaken. Mongolia and China began similar efforts to combat the encroachment of the Gobi Desert in 2006. Furthermore, President Franklin Roosevelt initiated successful Shelterbelt programs in the 1930s, using strategic planting of foliage to combat the land degradation caused by the Dust Bowl on the American high plains.

The Shelterbelt initiative, however, was successful because it supplemented its “green wall” policies with monetary incentives for farmers who changed their techniques to more ecologically sound production methods. The GGW initiative in Africa must be careful to similarly alter the behavior of land users, and not simply alter the land.

Kyle Benjamin Schneps is a dual master’s degree candidate at Columbia University specializing in international security policy and global health initiatives.