Desertification Flashcards
All 11 cards in this deck
Give one way climate change increases the risk of desertification.
Rainfall totals fall and become less reliable while higher temperatures increase evaporation, so vegetation dies and bare soil is exposed to erosion.
How does population growth on desert fringes lead to desertification?
More people means more land is grazed, cultivated and cleared for fuel, so the soil is never given time to recover.
How does the removal of fuel wood lead to desertification?
Trees and shrubs cut for cooking fuel leave the soil unprotected from wind and rain, with fewer roots to bind it together.
How does overgrazing cause desertification?
Too many animals eat vegetation faster than it can regrow, and their hooves break up the soil, leaving bare ground open to erosion.
How does over-cultivation cause desertification?
Growing crops year after year with no fallow period strips nutrients from the soil, leaving it dry, dusty and infertile.
True or false? Soil erosion is both a cause and a result of desertification.
True. Bare soil is blown or washed away, removing the fertile topsoil, which makes it even harder for plants to grow and exposes more soil.
Give one example of water management used to reduce the risk of desertification.
Drip irrigation, which delivers water straight to plant roots, wasting less water and reducing salinisation.
Give one example of soil management used to reduce the risk of desertification.
Leaving land fallow or rotating crops, and adding manure or mulch to restore nutrients and hold moisture in the soil.
How does tree planting reduce the risk of desertification?
Roots bind the soil and the canopy shelters it from wind and heavy rain, e.g. the Great Green Wall across the Sahel.
Give one example of appropriate technology used to reduce desertification.
Stone lines ('magic stones') along contours to trap rainwater and soil — cheap, made from local materials and easily maintained by local people.
True or false? 'Appropriate technology' means using the most advanced, high-tech equipment available to stop desertification.
False. Appropriate technology is small-scale, low-cost equipment that local people can build and maintain themselves, e.g. stone lines (magic stones).