A Plan to Slow the Creep of the Sahara—by Planting Gardens



This story initially appeared on Atlas Obscura and is a part of the Local weather Desk collaboration.

From the air, the brand new backyard within the city of Boki Diawe, in northeast Senegal, seems to be like a watch: broad open, unblinking, and flanked by a smattering of divots dug within the surrounding soil, darkish like freckles throughout a nostril. The bottom remains to be sandy brown, however close by, there’s a fringe of shiny inexperienced.

If all goes in keeping with plan, this backyard will quickly look equally lush. The round backyard—recognized domestically as a tolou keur—has not too long ago been planted with papayas, cashews, lemons, and extra. One of many internal curving rows is devoted to medicinal crops, whereas the outer row has been lined with baobabs and Khaya senegalensis, whose wooden is also called African mahogany.

The backyard is the newest iteration of the undertaking often known as the Nice Inexperienced Wall, first envisioned as a viridescent belt squiggling hundreds of miles throughout the Sahel area, from Senegal to Djibouti. Launched in 2007 by the African Union with backing from the European Union, the World Financial institution, and the United Nations, the undertaking was initially meant to assist stave off desertification by stymying the Sahara because it wandered south.

Desertification is the method by which lusher land degrades right into a desert. The phenomenon is nudged alongside by “an interaction of pure and human components,” says Chukwuma J. Okolie, a lecturer in surveying and geoinformatics on the College of Lagos in Nigeria. Okolie makes use of distant sensing information, corresponding to satellite tv for pc imagery, to trace landscapes tilting towards desert circumstances.

The drivers of desertification embrace local weather variability and local weather change, overgrazing, the development of river dams, and conflicts that displace folks and spur shifts in l and use. Lengthy droughts can go away fertile soil susceptible, and winds and rains can whisk it away. “Deforestation can speed up the method, as a result of bushes function windbreaks,” Okolie says. That’s the place the Nice Inexperienced Wall idea got here in.


The preliminary plan emphasised bushes as an anchor for soil and a buffer in opposition to the encroaching sand. Some parts of the thought made sense, says Geert Sterk, a geoscientist at Utrecht College who research land degradation. “Tree and shrub roots maintain soil, and the canopies lure raindrops earlier than reaching the soil floor and scale back sturdy winds,” curbing erosion by wind and the area’s comparatively uncommon however fierce rain, Sterk defined in an electronic mail.

However the formidable plan hasn’t actually panned out. There have been political squabbles about the place the inexperienced line needs to be drawn, and scientific debates about what fuels desertification, in addition to the efficacy of the strategy. As of 2021, the undertaking is only a fraction of the way in which in direction of its objective of planting a whole lot of thousands and thousands of acres.

A brand new infusion of cash, pledged earlier this yr by numerous governments and growth banks, will give the undertaking a lift—and now, the main focus is shifting to extra native gardens. Over the previous seven months, greater than 20 variations of those round gardens have sprouted throughout Senegal.

Aly Ndiaye, a Senegal-born agricultural engineer who helped design the tolou keur, instructed Reuters that the Nice Inexperienced Wall should be made up of smaller, productive gardens which might be “everlasting, helpful, and sequential,” a collection of sensible plots relatively than an unbroken line of bushes. Okolie agrees that the undertaking can’t be about shoving any seedling within the floor. He says it should entail “making an attempt to find the perfect species that may thrive” within the given soil circumstances and local weather, whereas additionally interesting to the individuals who will nourish them. Researchers have discovered that agroforestry initiatives usually fail when the main focus is solely on tree-planting and locals are overlooked of the method. “When the federal government crops bushes, it’s the neighborhood individuals who will maintain them” Okolie says. “The neighborhood has to take possession.”


Supply hyperlink