Chapter 7 - Deserts Flashcards
What does arable mean?
Land that is capable of growing crops.
What does arid mean?
Dry, parched climate or land.
What is atmospheric pressure?
The weight of the air on the Earth’s surface.
What is desertification?
The spread of desert lands and land degradation across more arable land.
What is an ecosystem?
A community of organisms interacting with one another and with the environment in which they live.
What is evaporation?
The process by which water turns from liquid to vapour.
What does nomadic mean?
A lifestyle where people move around an environment to a range of locations, usually related to the seasons and the availability of food.
What’s an oasis?
An area in the desert where groundwater is close to the surface and plants can grow.
What is a playa?
A flat basin in the desert that is covered in water every so often.
What does the term aeolian refer to?
Processes to do with the wind.
What is salinisation?
The process by which soil and water become salty due to salts moving in soils.
What does semi-arid mean?
The transition zone between desert and grassland that receives an average 250-500 millimetres of rain per year.
What does subsistence mean?
Crops or food grown to satisfy a community and not for sale.
What does subtropical mean?
Climates close to the Tropics of Cancer and Capricorn but not between them.
What does sustainable mean?
Using resources in a way that does not degrade them.
What is a wadi?
A stream or river course in the valley of a desert.
What is a xerophyte?
A plant adapted to living in the desert or in drought.
Who are the people living in the Kalahari desert?
The San
What has happened to the San people?
They are adjusting to Western culture.
What are deserts useful for?
Mining, agriculture, tourism, nuclear testing.
What resources can be found in deserts?
Common salt, sodium nitrate, borax, gypsum, diamonds, oil and natural gas.
What percentage of deserts are covered in sand?
20%.
Name 9 features of the desert landscape.
Barchan dune, longitudinal dune, star dune, Mesa, butte, arch, pedestal rock, badlands, wadi, playa lake, dust storm and oasis are all acceptable answers.
What’s an aquifer?
Groundwater flows under many deserts in layers of rock known as aquifers.
How much of the Earth’s surface is covered in desert?
About 30%.
What is the biggest desert?
The Sahara Desert, North Africa, 9 065 000 km squared.
Where are most hot, dry deserts found?
Near the Tropics of Cancer and Capricorn.
Why are hot, dry deserts also really cold at night?
There are large variations in temperature due to the lack of plants, cloud cover and moisture, which would normally trap heat near the surface.