Arid regions

The arid regions of the world occupy 26–35% of the Earth’s land surface. This wide range reflects various definitions based on climatic conditions, vegetation types, or the potential for food production. Much of this land lies between 15° and 30° latitude (Figure 4.1). Here the air which is carried aloft along the intertropical convergence zone subsides to form the semipermanent high pressure cells that dominate the climate of the tropical deserts.

Relevant technologies and techniques for agriculture in arid regions:

• Drip irrigation for water conservation
• Mulch to reduce water loss.
• Groundwater recharge, especially where there is seasonal or sporadic rain.
• Microtunnels, shading and other techniques for protecting plants from harsh sun and winds.
• Drought-tolerant vegetables

Other technologies for arid regions:

• Evaporative cooler in place of air conditioning