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How desertification works
by Dave Roos
Can Desertification be Stopped?
Is it possible to slow the progress of desertification or even stop it completely? Environmental experts say yes, but it will require a worldwide campaign to improve agricultural methods, regenerate plant life and conserve precious soil fertility.
The first step is to replace destructive agricultural techniques at the grassroots level. Poor farming communities in developing countries need to be taught the long-term benefits of crop rotation, the use of legumes and other cover crops to “fix” nitrogen back into the soil, sustainable irrigation methods, and techniques like terracing, which prevent water runoff and erosion in hilly, sloping landscapes .
Planting millions of trees in strategic locations could do wonders for halting the expansion of current deserts and preventing the creation of new ones. The Chinese government is currently planting a nearly 3,000-mile-long (4,828-kilometer-long) belt of trees along the edge of the Gobi desert to put the brakes on dust storms and prevent dune migration. A similar “green wall” is being considered along the frontier of the Sahara . On a smaller scale, simply planting trees around fields will cut winds that contribute to erosion of topsoil.
The most effective solutions to desertification are surprisingly low-tech. Researchers at a German university have developed a rehabilitation technique that relies on recycled coffee sacks. The sacks are filled with compost, seeds and a material that acts like a sponge, soaking up and holding rainwater for extended periods of time. The sacks can be dropped across the surface of a degraded dryland. Over time, as the sacks decompose and become drenched with rainwater, the seeds take root and spread out, fed by the rich compost .