Human uses of the desert in MEDCs
Case study: Las Vegas and the Mojave Desert
Las Vegas is an example of a city which is built in a desert area. Las Vegas is a fast-growing city – the population is expected to double in 40 years. It is located in the Mojave desert – one of America’s smallest and driest deserts, which has 15-25 cm of rain per year. To cope with the population’s demand for water, Las Vegas diverts the water supply from Lake Mead on the Colorado River.
650,000 people live in the desert. In addition the Mojave desert is used by:
- tourists – visiting areas such as Death Valley
- military, as they test out airplanes and train troops
- hikers and rock climbers
- off-road vehicles – including quad bikes and motorcycles making use of the varied terrain
- solar and wind energy generation
- film makers, attracted by the scenery
The way deserts are used presents many challenges. The off-road vehicles damage the sensitive desert ecosystem. The growth of urban areas threatens the desert area, and pollutes the air. The demand for water increases. The city officials have encouraged the use of recycled waste water and the removal of water thirsty lawns. Fibre optic cables are routed through the desert connecting urban areas – disrupting the fragile ecosystem and allowing weeds to grow.
Human uses of the desert in LEDCs
Case study: Thar Desert, India
The desert has a population density of over 80 people per km2. (Other deserts have population densities below 10 per km2). There are many mobile sand dunes, and sandy hills.
The desert area is not very fertile. Soils are quickly drained, and contain few nutrients. The farming is limited, typically a few animals on more grassy areas and fruit. Most is subsistence farming.
Commercial farming has been possible since the building of the Indira Ghandhi Canal. This irrigates an area near Jodhpur. Wheat and cotton can be grown. The canal also supplies drinking water.
Mining and industry
Resources such as limestone and gypsum (for making plaster) are found in this desert – and are valuable for the building industry.
Tourism is a growing industry, and locals can act as guides and provide transport – such as hiring out camels.
Soil erosion and salinisation
There are many issues when humans use deserts and their surrounding areas.
This is a problem which affects many areas. When the soil is left bare, the wind can pick up speed due to the flat land and blow away the unprotected soil.
The effects of drought in Africa
- The soil is exposed and vulnerable to erosion as a result of the removal of vegetation and overgrazing.
- Trees, which provide protection from the wind and rain, are removed to be used asfuel.
- Nomadic tribes have become more sedentary, which puts pressure on the land where they settle.
- When soil is blown away the land becomes useless for grazing and crops and causesdesertification. This is a problem in the Sahel region of Africa. This problem is worsened when restrictions are placed on the movement of nomadic tribes.
Salinisation occurs when the water in soils evaporates in high temperatures, drawing salts from the soil to the surface. These salts are toxic to many plants and make the land unusable. This has consequences such as low yields, poor profits and even starvation. Irrigation of land – when water is brought to land that is naturally dry – can cause salinisation on desert margins. It is not just physical geography which is affected when humans use desert environments. Culturally, when tourists and new migrants come in culture may be diluted or new languages picked up.
With a growing population there is more demand for food and water. This puts pressure on fragile and limited resources. Overgrazing and overcultivation to provide enough food are two problems caused.