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Flashcards in hot deserts Deck (7)
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1

what are methods of reducing desertification?

- water management - growing crops that need little water can reduce water use
- drip irrigation on crops - means soil isn't eroded by lots of water being added all at once

- tree planting - trees can be planted to act as windbreaks - reducing wind erosion

- soil management - leaving areas of land to rest in between grazing or planting them lets them recover their nutrients

- appropriate technology - involves using cheap. sustainable, and easily available materials to build things easy for local people to maintain

2

how are plants adapted to cope with hot + dry conditions?

- plant roots can be extremely long to reach deep water supplies
- many plants succulents - have large fleshy stems for storing water + thick waxy skin to reduce transpiration

- some plants have small leaves to lower surface area to reduce transpiration

- some plants only germinate after it rains + grow quickly it make most of wet conditions

3

how are animals adapted to cope with high temp + limited water?

- nocturnal animals stay cool when sleeping when hot
- many desert animals have long limbs giving large SA to lose heat from

- lots of animals live in underground burrows - temps less extreme

- some bigger animals store fat that they break down into water (camels)
- some animals get water from their food
- most desert animals minimise water loss through sweat + urine

4

what are the causes of desertification?

- climate change - reduce rainfall and rising temperatures have meant less water for plants
- fuelwood - people rely on wood for fuel - removal of trees causes soil to be exposed

- overgrazing - too many animals mean plants eaten faster than can grow back - causing soil erosion

- over-cultivation - if crops grown in same areas too often - nutrients in soil will be used up - causing soil erosion

- population growth - a growing population puts pressure on the land leading to more deforestation, overgrazing and over-cultivation

5

what is desertification?

means turning of drylands into deserts

6

what are opportunities for development in the sahara desert?

- mineral extraction - morocco world's largest exporter of phosphate - holds 75% of worlds phosphate reserves
- tourism - many people fascinated by remote + exotic desert locations

- energy - Algeria is a leader in oil exploration + extraction in the Sahara - 60% of Algeria's income from oil & gas industry - solar energy can be exploited in Tunisia because Sahara receives 12 hours of sunlight per day

- farming - water essential for plant growth so commercial agriculture in Sahara only possible where enough irrigation of water

7

what are challenges for development in the Sahara?

- extreme temperatures - Sahara's temp can reach 40C during day and can drop to below 0C at night - can cause illness/death - often too hot for tourists so people with job only work some months

- water supply - low annual rainfall - most rivers only flow for part of the year - difficult to provide water for workers, industry + irrigation

- accessibility - sahara huge - providing services hard - only a few roads - people + material have to travel long distance - air - expensive