Hot Deserts Flashcards
Why is the hot desert hot and dry?
High pressure belts- sinking air
Continental interior- clouds lost moisture
Rain shadows- mountains shield areas
Why is it hot in the day and cold in the night?
No cloud coverage
Day; sun’s direct rays
Night; nothing to retain heat
How is a cactus adapted?
Spines instead of leaves; deter predators. Reduce water loss due to small surface area
Extensive roots absorb water
Can expand to store water when it rains
How are animas adapted?
Fennec fox- nocturnal, large ears to cool down easily, large feet to not sink in sand
Camel- skin between toes to not sink, long eyelashes to protect from sand, hump to store water and fat- 3 weeks of food
What are 4 causes of desertification?
Unreliable rain
Deforestation
Over farming
Poor water management
How does unreliable rain cause desertification?
Water stress; less plants
Soil blows away and fertility degrades
Not enough crops and plants made
How does deforestation lead to desertification?
Vegetation retains soil fertility, as tree roots help to stabilise soil
Also nutrient cycling keeps it fertile
Deforestation begins cycle of degradation
How does over farming lead to desertification?
Farmers continue to reuse soil
Don’t give time for land to recover
Little grows
How does poor water management lead to desertification?
Irrigation increases salt in soil
Rivers and lakes dry up
What are 4 ways to reduce desertification?
Terrace farming
Irrigation schemes
Bunds
Afforestation
How does terrace farming help stop desertification?
Conserves water- no surface run off
Soil maintains nutrients as it has time to soak up water
How do irrigation schemes help stop desertification?
Reservoirs store water
Drip system onto plants- doesn’t waste water, and is specific
How do bunds help reduce desertification?
Reduce soil erosion as it is a windbreak
Keeps soil in one area
Trap moisture
How does afforestation reduce desertification?
Tree roots stabilise soil
Nutrient cycle retains soil fertility
