U1- Extreme Environments Flashcards
What is a tundra?
A biome with no trees.
It is basically a polar grassland with dwarf shrubs, mosses, lichens and flowers.
Who are the indigenous people?
People who still live traditionally in some places although may have moved to towns.
Who are the Aleuts?
People of Alaska and Russia who are skilled in using every part of a seal or whale- even the bones are used for making needles and weapons.
Define extreme environment.
An extreme environment has harsh and challenging conditions.
Humans, plants and animals need to adapt in order to survive. Two extreme environments include polar and desert climates.
How are Arctic flora adapted to polar extremes?
Trees in coniferous forest biome:
- Small leaves/needles to limit water loss.
- Thin at the top to bend in strong winds.
- Cone shaped to help shed snow.
- Shallow roots to avoid permafrost.
- Evergreen leaves so photosynthesis can start as early as possible in growing season.
Tundra biome:
- Low to ground to keep out of cold wind.
- Flowers can twist to follow the Sun.
- Cushion shape to trap warm air in the centre.
Give three examples of Arctic flora.
- Arctic willow.
- Arctic poppy.
- Cushion plants.
How are polar bears adapted to polar extremes?
- Fur on soles of feet➡️Better grips on ice and for insulation.
- Small SA:Volume ratio➡️Reduces heat loss.
- Large feet➡️Spreads the load on snow and ice.
- Sharp claws and feet➡️Catching and eating prey.
- Small ears➡️Reduces heat loss.
- Strong legs➡️Helps catch prey.
- Thick layer of fat➡️Insulation and store of energy.
- Thick layer of white fur➡️Insulation and as camouflage.
- Dens dug into snow or caves- not permafrost.
How have Nenets adapted to polar extremes?
- Transport everything using sleds.
- Portable teepees made of reindeer skins.
- Fireplace inside teepees➡️Temperatures can reach 25oC.
- Make their own tools, sleds, etc.
- Walk on skiis.
- Set traps to catch meat.
How are buildings adapted to polar extremes?
- Triple glazing and very thick insulation➡️To keep heat in and cold out.
- Roofs sloping➡️To shed heavy snow.
- Built on a gravel pad or on stilts➡️Heat from house does not melt permafrost.
- Water, sewage and power are in a utilidor box above the ground➡️Repair access is easier and permafrost is not melted.
*Traditionally houses either temporary igloos or mobile animal skins*
How is clothing adapted to polar extremes?
Traditionally clothing was made from animal skins.
Today modern hi-tech insulated clothing has replaced traditional clothes.
Gloves, hats and layers are essential to protect against frostbite and hypothermia.
How is energy used in polar extremes?
Oil and gas are the main energy resources because renewable energy is unsuitable to polar areas.
Energy demand for heating and transport is high.
How is transport adapted to polar extremes?
Skis, dogs and snowmobiles are used in summer.
Driving is suitable in winter because the ground is frozen.
‘Ice roads’ cross frozen lakes, rivers and sea so heavy goods can be transported.
What farming and food is used in polar extremes?
Arable farming is not possible.
Inuit diet.
Reindeer herding traditional.
Describe the key physical characteristics of a polar climate.
Polar regions have low precipitation- less than 50mm a year. It often falls as snow in the long winter due to sub-zero temperatures.
Precipitation is caused by air rising, but as cold polar air is dense, it sinks towards the ground. This creates high pressure and therefore a lack of precipitation.
Many polar places have a summer of only 4 months with the other 8 months having an average temperature of below 0oC.
Describe the key physical characteristics of the Australian desert.
In a hot, arid desert, rainfall is less than 250mm a year and temperatures are often over 40oC.
Semi-desert regions are found around the fringes of deserts and get 500-700mm of precipitation a year. In these regions most of the precipitation falls in a short rainy season and the rest of the year is dry.
How/why does Australia have deserts?
- Rain bearing winds blow across the Pacific towards Australia.
- The mountains that border the coast (The Great Dividing Range) cause this air to rise and cool rapidly.
- This leads to condensation, then rain.
- As the air descents from the mountain, it is drier and a ‘rain shadow’ is created.
- This results in low rainfall in western areas.
- The further west the winds blow, the drier they are, so the driest areas are in western Australia.
What 3 main ways have flora adapted to arid climates?
- Succulence.
- Drought Tolerance.
- Drought Avoidance.
Australia has over 400 succulent species.
How are succulent plants adapted to arid climates?
- Store water in fleshy leaves, stems or roots.
- Stems and leaves have waxy cuticles which make them almost waterproof.
- Succulents can quickly absorb large amounts of water through extensive, shallow root systems➡️They can store this water for a long time.
- Succulents are attractive to thirsty animals, so most have spices, are toxic or camouflaged.
- Succulent species’ metabolism slows down during droughts and their stomata remain closed to reduce water loss.
How are drought tolerant plants adapted to arid climates?
- Most shed their leaves to prevent water loss through transpiration.
- Eucalyptus’ remain evergreen but have waxy leaves with few stomata to reduce water loss.
- Photosynthesise with low leaf moisture level, which would be fatal to most plants.
- Have extensive, deep roots which penetrate soil and rock to get to underground water.
How are drought avoiders adapted to arid climates?
- Seeds last for years, and germinate only when soil moisture is high.
- Some germinate during autumn after rain and before the winter cold sets in- the seedlings survive winter frost and flower in spring.
- Most are annuals- they survive one season, have a rapid life cycle and die after seeding.
How are plants adapted to desert extremes?
- Stomata on both sides of leaf.
- Leaves contain toxic compounds➡️To stop from being eaten.
- Waxy leaves on both sides➡️To minimise water loss.
- Small leaves➡️To reduce water loss.
- Leaves hang vertically➡️Reduced exposure to the Sun, reducing transpiration.
How is the Bilby adapted to desert extremes?
- It is nocturnal, sheltering from the daytime heat to avoid dehydration.
- It has low moisture needs which are obtained from its food such as bulbs, fungi and insects.
- It burrows for moister, cooler conditions.
How is the Perentie adapted to desert extremes?
- To escape the desert heat, it burrows or hides in deep rock crevices.
- It has low moisture needs.
- It hibernates from May to August to avoid cold.
How is the Red Kangaroo adapted to desert extremes?
- It feeds at dawn and dusk where the air is cooler, and sleeps during the heat of the day.
- It survives by hopping (a fast, energy efficient form of travel).
- Dew is an important part of its water intake.
- Rain triggers a hormonal response in females, so that breeding only occurs during rains.
How is Coober Pedy an example of how people have adapted to the Australian desert climate?
- 60% of the town is 8-22ft underground.
- Places to eat, drink, sleep, 2 underground churches and 1500 family homes are all underground.
- Economy relies on opal➡️opal capital of the world.
- There are air shafts above the surface to allow people to breathe.
- 40inch thick pillars to support and walls are soundproof.
- No sewage, so bathroom must be on ground level.
How is transport adapted to desert extremes?
- Light aircraft and trains are more reliable than cars.
- Traditionally used camels.
- Modern vehicles are usually 4x4.
What is the traditional diet of the Aboriginals?
- Fruits➡️Bush tomatoes and bush bananas.
- Seeds➡️Wattle seeds and sandalwood nuts.
- Grubs➡️Witchetty grubs are eaten raw or cooked.
- Meat➡️Traditional wild animals such as kangaroo or emu.
What are the beliefs and lifestyle of the Aboriginals?
- Traditionally, aboriginal people survived by hunting and gathering.
- They used fire to drive out animals for hunting, to clear wood and allow grass to grow.
- As a result, fire-tolerant plants came to dominate the landscape. These re-grow quickly after fire.
- Aboriginal crafts were based on hunting or music and tribal celebrations.
- Their customs and stories were spoken, never written.
