When productive land quickly loses topsoil and plant life, scientists call this desertification. It can happen in arid (dry) and semi-arid regions of the world. One-third of Earth’s land area in more than 100 countries (including the United States) is at risk of desertification.
Desertification is a natural process that is associated with global climate change. With time, as the climate changes, even forests may become deserts.
Desertification can also be brought on by improper management practices. Animals such as cattle, sheep or goats sometimes take over grasslands. This might result in overgrazing: animals harvest too much grass. Degraded rangeland conditions are the result. Without sufficient plant growth to cover the soil, wind and water erosion will occur. The historic Dust Bowl of the 1930s was a result of desertification caused by over¬grazing and excessive tillage. The worst of the Dust Bowl hit Texas, Oklahoma, Kansas and Colorado, but prairie states all the way to the Canadian border as well as the Canadian Prairie Provinces were affected.
Following good farming and property management practices can prevent most desertification. One example is to keep livestock out of sensitive areas and provide livestock with alternative locations for water. Landowners should make sure soil has adequate vegetation covering it to prevent accelerated erosion by wind and rain. China is taking some steps to address desertification with crop cover and with plans to plant trees along the border of the Gobi Desert to help decrease dust storms and desertification. China and Africa face some of the most severe challenges.
Controlled grazing can also help. Controlled grazing addresses the timing and duration over which animals have access to a pasture. This can be achieved by rotating animals so they graze in one area so that grass in another area has time to regrow. Likewise, farmers should rotate where they grow their crops so that the soil is able to “re-charge”.
Proper range management will not reverse the effects of global climate change; however, in the short term, it can decrease soil degradation and slow the advance of desertification. We need to prevent desertification so we continue to have fertile soil to grow food for the worlds’ population, and to prevent disasters like the Dust Bowl.
-Answered by Eric Brevik, Dickinson State
To view SSSA’s “Soils and Climate” video, visit https://youtu.be/T4A_rMlHcyE.
To perform a classroom activity about desertification, visit https://www.soils.org/files/sssa/iys/unesco-desertification-activities.pdf.
More educational materials can be found on various SSSA websites:
http://soils4teachers.org/ (K-12 Lesson Plans and Activities)
http://soils4kids.org (Just for kids!)
http://soils.org/iys (International Year of Soils, with a coloring book and monthly ideas for teachers and scientists!)
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