Read at : Google Alert – desertification
Saturday, October 18, 2008
Global Desertification by Frank B Lee
Imagine a world of deserts…
General Information about Desertification
Desertification is the breaking down of land by erosion. It most often occurs in dry areas, where human activity or climate change (or both) has greatly impacted an area. The freshwater supply and the soil can be easily destroyed, and if the land is degraded, the drylands will be unable to renew the water and soil resources and become a desert. Because of the loss of plants and trees by human activity, erosion also destroys most of the topsoil of the dryland, disabling any vegetation, leading to famine and loss of biodiversity in the area.
What Causes Desertification?
The main causes of desertification are overgrazing of livestock, overcultivating crops, deforestation, the increasing amount of fires per year, overusing groundwater, increasing amount of salt in the soil, and climate change. Overgrazing and fires causes destruction of plants in the drylands, destroying the biodiversity of the dryland. Overcultivating and an increase of salinity can lead to the destruction of the topsoil which is important for growing crops. In vegetated areas, the land is often cooler than the rest of the dryland and prevents the dryland winds to erode the topsoil. Climate change and droughts can cause a decrease in freshwater amount, which will prevent plants to grow.
All these processes involve the overpopulation of the drylands. Where there are more humans, there will be destruction of the drylands.
What is Being Done to Stop Desertification?
To stop desertification, we must look at what causes desertification. There is no other way to remove the effect of overgrazing or overcultivating the land except by not using the land. This is not a smart way to stop desertification, as humans need the food and other resources that come from the drylands. However, to stop the erosion, there have been some tree belts, strings of trees that block wind from blowing away the topsoil in the drylands. In north-eastern China, there will be “Green Wall of China” that will be grown. It is a wall of trees that is almost as long as the Great Wall of China. For the loss of freshwater, humans should use the idea of sustainable resources so that water can be saved. Also, in some areas, leguminous plants have been used to extract the nitrogen from the atmosphere into the soil to restore the fertility of the soil. Also, to combat deforestation, people have been using the heat as an advantage with solar cooking instead of using wood for fuel.
How Has Desertification Affected Us?
Desertification is like a monster, eating up the land that it passes through. It’s worse than a hurricane, an earthquake, or a fire. Once it somewhere, it’s really hard to get that place back, because it makes plants hard to grow there by destroying the soil and things can’t live there because there is no water.