Hot deserts

• Where are hot deserts found?

  They are mainly found in a belt between 30° degrees north and south of the equator, usually in dry continental areas
• What are the characteristics of hot deserts?

  • Very little organic matter and humus
  • Below 250 mm annual rainfall
  • Very high diurnal range due to no clouds trapping heat at night time
  • Infertile and saline soils due to salinization where high rates of evaporation draws salts into the surface
  • Low biodiversity with about only 5000 to 6000 plant species and many succulents
• How is interdependence found in hot deserts?

  • Very slow nutrient cycle stems from limited producer growth due to a lack of water, extreme temperatures and inappropriate soil features
  • Vegetation roots bind to soil and makes it stable, preventing wind and soil erosion
• What is meant by desertification?

  The process of fertile land gradually turning into an arid desert
• What are some causes of desertification?

  • Overgrazing
  • Overcultivating
  • Population Pressure
  • Climate change
• How does overgrazing lead to desertification in the Thar desert?

  Nomadic people in the Thar desert frequently move their homes and livestock but as the number of these people decrease, more animals will stay on fertile lands for prolonged periods of time. It exhausts the soil and strips it of its nutrients and decreases quality which turns to arid land later on. For example, 54.5 million livestock live in the Rajasthan state
• How does overcultivation lead to desertification in the Thar desert?

  The Thar desert is famous for its cotton and wheat production. When farmers use the same area of land to grow crops repeatedly, without giving periods of rest, this exhausts the soil and decreases its quality. This causes little to no crops to grow and leaves the soil bare which means it is now more vulnerable to wind and soil erosion
• How does population pressure lead to desertification in the Thar desert?

  The Thar desert is the most densely populated desert in the world, with about 83 people per km2 squared. As the population increases, more crops are needed to be cut down and used as resources for the growing population and this in turn leads to topsoil becoming exposed and susceptible to wind and soil erosion through the lack of vegetation which acts as a cover for the soil.