Desertification is a process in which semi-arid arable land becomes deserts, unable to sustain plant or animal life. Although desertification can be caused by natural processes, such as climate change, it is generally accepted that human influences drastically accelerate the rate of desertification worldwide. As pressures on Earth increase due to population growth and global warming, it is estimated that the rate of desertification could begin to rise rapidly and is already causing serious social and environmental problems in some African countries. .
In the United States, one of the most famous historical examples of desertification is the Dust Bowl of the 1930s, although the rapid destruction of prairies in the American West is comparable. In Africa, the rapid expansion of the Sahara and severe desertification in the Sahel region of West Africa are cited by many humanitarian organizations as issues of concern. For humans, the reduction of land usable through desertification has a serious impact, especially on impoverished indigenous populations who cannot easily adapt to new life systems.
Desertification often begins in drought conditions, although it does not always occur in times of drought. The top layer of hardy plants is removed from the soil, which means there are no roots to hold the soil in place. Winds transport nutritious plant land to other places, leaving sand behind and forming large drifts of sand and dead plant material that invades human civilization. Animals are unable to feed in these conditions, which means that nomadic peoples lose a large part of their herds, and since all plant life is dead, there are no alternative sources of food. The soil also has a higher risk of flooding and erosion begins to clog nearby water sources with soil.
Climate change is obviously a factor in desertification, but so are harmful human practices, such as poorly practiced irrigation, which concentrates salts in the soil and kills plants. In addition, deforestation and land clearance of all available plant life also contributes to the problem. Especially in the delicate transition zones between arid desert and fully arable land, desertification can occur very quickly and be completely irreversible. As the topsoil disappears with the plants, the desert is unable to retain even a minimum of water supply and quickly becomes completely arid.
Many humanitarian organizations, including the United Nations, are making efforts to end desertification and try to reclaim usable land. These include education on land use and recovery tactics, such as embedding straw mats and retaining walls on the floor to prevent it from getting windy. Plants with robust roots are also planted in order to keep the soil in place. There are also numerous campaigns to eradicate hunger, as desertification poses serious risks to good nutrition: food deliveries and nutrition education are offered in areas affected by desertification, in the hope that the supply of food give the opportunity to recover in delicate transition areas.