Resources and environment, Year 10: development and desertification (Hot deserts option)

Strong sunshine and cloudless skies nearly all year

提示What do the panels need, and what never gets in the way here?

为什么Deserts also have large areas of empty, flat land for solar farms. Energy is one of the four development opportunities AQA names; the others are mineral extraction, farming and tourism.

irrigation

提示It begins like "irritate".

为什么With it, the long hot growing season of a desert becomes an advantage and crops can be grown all year. Without it, commercial farming in a hot desert is impossible.

An aquifer

提示Its first four letters are Latin for the liquid it holds.

为什么Many desert farms and towns depend on one. The water may have collected thousands of years ago. If it is pumped out faster than rain refills it, the level drops and the supply will not last.

It evaporates before the crops can use it

提示Puddles vanish fast on a scorching day.

为什么This links two of AQA's challenges: extreme temperatures and water supply. Drip irrigation, which feeds water through pipes straight to the roots, wastes far less. Extreme heat also limits the hours people can safely work outdoors.

Workers, equipment and the product must all travel long distances, with few roads

提示Far from ports and towns, and little tarmac.

为什么Roads, railways, pipelines and airstrips often have to be built before any work can start. Use this framework for your own case study: name the opportunity, then explain which challenge makes it expensive.

Desertification

提示A long word built from the name of the dry land it produces.

为什么It happens in dry regions that still get some rain, where the plant cover is already thin. It is caused by a mix of climate and the way people use the land.

Animals eat the plants faster than they regrow, leaving bare soil for wind and rain to remove

提示Too many goats, too little grass.

为什么Plant roots bind the soil and leaves shelter it. Hooves also trample the ground hard, so rain runs off and does not soak in. Once the fertile top layer has gone, grass cannot return.

More fuel wood is cut than can regrow, so the tree cover that protects the soil is lost

提示Extra cooking pots, fewer branches.

为什么Trees shade the ground, break the wind and hold the soil with their roots. As nearby trees disappear, people walk further for wood and the cleared area widens around each village.

cultivation

提示A noun from the verb for tilling and planting.

为什么In the past, land was left fallow for some years so that it could recover. With more people to feed, there is less land to spare, so fields are used without a break. Worn-out soil grows little, is left bare and blows away.

They slow the water running downhill, so it soaks in and the soil it carries is trapped

提示A tiny dam for each rainstorm.

为什么Rain in these regions comes in short, heavy storms and runs straight off hard ground. Each line holds the water back for a while. Soil builds up behind the stones and crops grow better there. This is both water management and soil management.

It is cheap, uses local materials and skills, and local people can build and repair it

提示Could a village make and mend it without outside help?

为什么Expensive machines can fail when there is no money for fuel or spare parts. A simple method that people already understand carries on working. Tree planting can work the same way when local people choose and look after the trees.