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Topic 2 Geo: Earth's resources - Coggle Diagram
Topic 2 Geo: Earth's resources
2.1: Earth's natural resources
Natural resources - Something that occurs naturally, without any help
2.2 Water around the world
97% of the Earth's water is salt water
3% is fresh water, but 2% of it is in ice sheets and glaciers
only 0.1% of the waters are in rivers and lakes
What do we use fresh water for?
Agriculture (70%)
Industry (19%)
Other uses (washing, flushing, drinking) (11%)
2.4 The growing water challenge
Reasons why we need more water now
growing population
Developed countries have more meat demand. Meat is
6times the water needed as to produce rice
Developing countries also need more goods.( Washing machines, cars, device and gadgets) industry uses a lot of water to produce them
2 types : Economic water scarcity and physical water scarcity.
Economic water scarcity is normally linked with poverty
1/8 of us do not have clean safe supply of water.( 900million people)
Living in countries that cannot afford piping clean safe water to everyone. So people collect dirty water from ponds and rivers. The water may be infected and causes disease.
They will need to walk a long way to get the water and the buckets are very heavy to carry
Most poorer countries are now making water supply a priority
Physical water scarcity means an area does not have enough water. How to solve this?
Use water more wisely
Water crops when they need it. For example, sensors that monitor leaf temperature can turn off sprinklers when it reaches a limit
We can also use less water at home. For example in the showers, kettles, washing machine and etc.
Use greywater to flush toilets or water your plants
Grow crops that need less water
Bring water in from other places
For example, China has a project to move water from the Yangtze River to the dry northern parts of China(Over 1000km)
Use saltwater
Remove the salt in saltwater so it can be used. This process is called Desalination. It needs a lot of electricity so it is mostly used in coastline countries.
Develop crops that tolerate saltwater. (For example potatoes)
2.5 Soil
Soil provides nutrients that plants need. It also provides water and oxygen. If one of the things mentioned is missing, the crops will fail.
We are destroying soil. Here are a few examples:
We bury soil under concrete and once its buried it will remain there.
We contaminate it and bury rubbish in it on landfill sites.
We cut down trees and other plants that protect it. So it gets eroded
Overgrazing
We grow crops after crops until it has no nutrients left.
2.6 Desertification is the drylands
Sahel is a region which is in the south of Sahara Desert. It is one of a drylands on Earth. Drylands are not deserts, but they don't get a lot of rain, and the amount is variable.
Drylands cover 41% or the Earth's land surface, and they are home to 1/3 people.
2.7 The fight against desertification
The problems faced
Earth is expected to gain 2.5billion more people, between 2015-2050. And they all need food.
Most of the population rise will be in the poorer countries and most of them have drylands.
Drylands are losing more and more land every year to desertification. And this is affecting over a billion people.
How to solve?
Plant trees and bushes. They protect soil from erosion, and helps rain soak into soil.
Store any rain that does fall. Dig shallow pits to trap rain and plant in the pits
Irrigate if you can. Use drip irrigation so water drips beside the roots from tiny holes.
Plan grazing. Let an area be heavily grazed for a short time then move the animals to the next place. The manure helps the soil
These methods usually don't cost much and they are easy to learn. If enough people around the world fight desertification and look after the soil, maybe we can avoid world hunger in 2050.
2.8 Oil as energy
We depend on oil
We depend on oil to go places( Petrol, diesel, jet fuel, fuel oil) They all come form oil.
Some power stations burn oil for electric, and central heaitng in homes uses oil too.
Oil is also the used for medical drugs, plastics, synthetic fabrics, gels, and more.
Who has it?
Canada
USA
Russia
Algeria
Libya
Kazakhstan
Iran
Iraq
Saudi Arabia
Nigeria
Angola
These countries have over 90% of the oil over the world.
Bad sides using oil
When it burns it produces carbon dioxide. This gas is the main cause of global warming
It also produces Sulphur dioxide, which gives us acid rain
Oil spills pollute the environment
Some oil-producing countries are politically unstable so we can't, or able to buy oil form them. (No steady oil supplies)
2.9 Renewable sources of energy
Renewable resource: A resource that nature can continually provide(such as sunlight) or something we can grow more(like trees)
Sources of renewable resources:
Power stations that burn biomass( straw, wood..) or waste instead of fuels
Hydroelectric station that uses fast-flowing water to spin the turbines
Wind farm uses the wind to spin turbines
Waves making turbines spin off the coast, and the energy flows into a central hub and to the land
Tides spin turbines underwater
Solar farms uses the sunlight to strike solar cells, which turns into electric currents
Governments aim to cut down fossil fuels and get energy from renewable sources.