Photo credit: WVC 2001-07
TC-Dialogue Foundation (Belgium) project in Pakistan (GADAP)
Soil conditioning training of local farmers (use of TerraCottem)
What Causes It
Desertification is when a grassland becomes a desert. Many grasslands throughout the world survive on only a few inches of rain per year more than a desert. Yet they provide grass for countless animals. The grass also holds the soil in place, preventing erosion. Sometimes, a long dry spell will affect the grassland to make it turn desert, but scientists have found that much of the world’s desertification is due to the actions of humans.
Over-grazing does the most damage to grasslands that experience desertification. If a dry grassland is overgrazed by cattle, horses and sheep, it loses the little protection it has against erosion. The plant roots that help the soil stay in place are lost so it blows away and washes away. Soon you have a new desert. Clearing forest can have a similar effect if all the vegetation is taken at once. This is done with the slash and burn technique for clearing land. The topsoil blows or washes away. An entire river valley can turn to desert if the river is rerouted upstream for agricultural irrigation or drinking water for a nearby urban area. More than 40% of the Earth’s land is thought to be dry (arid or semi-arid) and has more than 2 billion people living there. Scientists think that 24 billion tons of topsoil are lost to erosion every year.
How Does It Affect Us
In the United States, in the 1930s, the great plains underwent a drastic desertification from too many animals grazing it at once, too much plowing under of the natural prairies at once and then an unusual drought. This caused the dust bowl that lasted for ten years and fueled the great depression. So, desertification can affect the humans that cause it and in turn cause terrible hardship to those humans — us!
Read the full article: Exploring Nature
Author: Willem Van Cotthem
Honorary Professor of Botany, University of Ghent (Belgium). Scientific Consultant for Desertification and Sustainable Development.
View all posts by Willem Van Cotthem