DESERT PROCESSES

Another area of extreme landscapes that I am not so confident with is desert processes and landforms. Now I have revised a few desertification processes but do not remember them in great detail, I am hoping my current basic knowledge may relate to and help enhance my knowledge on these processes.

So what is desertification?

Sahara Desert

Desertification is caused by a combination of drought and poor use of land. It takes place when climatic and human processes reduce the ability of the land to support vegetation.

In terms of droughts, a drought occurs when the rainfall is below its average for two consecutive years. If a drought lasts for so many years, ecosystems cannot cope and start to shut down due to the lack of water.

Human factors affect the landscape too, these include:

• Overcultivation – If too many crops are planted, it can exhaust the soil to the point where it struggles to/or can no longer support vegetation.

• Deforestation for firewood also strips the lands vegetation, further exposing the soil allowing erosion to occur. The increasing population is creating a higher demand for firewood to rise.

Other factors:

• Overgrazing - The rearing of too many animals results in overgrazing, which means the soil is more likely to undergo erosion as there are few bushes and little grass to protect it.

• Climate change – In some areas, the climate is becoming much drier due to lack of rainfall. Less rainfall results in poorer grazing and a reduction in crop production.

When looking at desertification, a useful source is the guardian which provides information on a range of areas around the world that are suffering from lack of water, some of these places include Las Vegas, the United States and China. See: http://www.guardian.co.uk/environment/desertification

Students may find a video by the President of the International Fund for Agricultural Development (IFAD) useful when trying to understand desertification and how people, particularly farmers, can try to prevent the processes happening. This can be found on: http://www.unccd.int/en/Pages/default.aspx

A useful PowerPoint slide that I have found that has been used to teach this for GCSE can be found on: http://www.slideshare.net/chestertoncc/desertification.

Links:

http://www.eden-foundation.org/project/desertif.html

http://www.guardian.co.uk/environment/desertification

http://www.unccd.int/en/Pages/default.aspx