Unit 3B - Human And Their Environment Flashcards
What is the two biggest causes of the rate of the world population growth and why?
Modern medicine and farming methods as it has reduced the number of people dying from disease and hunger
How is the worlds population growing?
Very quickly, exponentially
An increasing population causes what on the demands of the environment?
The demands increase
The effects of human activity used to be small and local, what are they like now?
They have a far more widespread effect
Why are we taking more resources from the environment?
Increasing population means we need more resources to survive but also we demand a higher standard of living which use more resources and energy
As well as increasing the demand on the environment what else does a rapidly increasing population cause?
Us to produce more waste
As we are producing more waste what does this effect and why?
The water, land and air because of harmful population
What effect does more waste have on the water?
Sewage and toxic chemicals from industry can pollute lake, rivers and oceans which affects the plant and animals which rely on them for survival and chemicals used on land like fertilisers can be washed I to water
What effect does more waste have on the land?
We bury nuclear waste unground and we dump a lot of household waste into landfills
What effect does more waste have on the air?
Smoke and gases released into the atmosphere can pollute the air
What are the four main human activities the reduce the amount of land and resources available to other animals and plants?
Building, farming, dumping waste, quarrying for metal ores
Why isn’t the greenhouse effect all bad?
We need it to keep the earth a suitable temperature for living on
How is carbon present in the atmosphere?
As carbon dioxide
What does too much carbon dioxide in the atmosphere cause?
Global warming and the greenhouse effect
What are the five places that naturally stores carbon dioxide?
Oceans, lakes, seas, peat bogs and green plants
What’s another way for saying carbon dioxide is locked up in natural stores?
It is sequestered in natural stored
Why are the natural stores of carbon dioxide really important?
It means that carbon dioxide is removed from the atmosphere
What is the temperature of the earth a balance between?
The heat it gets from the sun and the heat it radiates back out into space
What makes the gases in the atmosphere like an insulating layer?
They absorb most if the heat that would normally be radiated out into space and re radiate it in all directions
Why is it important that we have some gases in our atmosphere to act as an insulating layer?
If it didn’t happen they’d be nothing to keep the heat in at night and so we would get very cold
What are the gases called in the atmosphere which help keep the heat in?
Greenhouse gases
What are the two main greenhouse gases which levels are rising very quickly?
Carbon dioxide and methane
What is the main cause of global warming?
The increasing greenhouse gases
What is another type of climate change that global warming can cause?
Changing rainfall patterns
What is deforestation?
The cutting down of forests
What are the main three reasons deforestation happens?
- ) It provide timber to use as building material
- ) to clear more land for farming
- ) to produce paper from wood
Why is it important to clear more land for farming?
It provides more food and more crops which can be used in biofuels
What are the four main problems caused by deforestation?
- ) more methane in the atmosphere
- ) more carbon dioxide in the atmosphere
- ) less carbon dioxide taken in
- ) less biodiversity
What two reasons are they for that deforestation leads to more Nathan in the atmosphere?
The land is cleared for farming, some of the fields have chattel which produce methane and rice which is grown on the fields is grown in warm, waterlogged conditions ideal for decomposers, these organism produce methane
What two reasons are there for that deforestation causes more carbon dioxide to be in the atmosphere?
Carbon dioxide is released when trees are burnt to clear land and the microorganism that feed on dead wood realises carbon dioxide as a waste product of respiration
Why does deforestation mean less carbon dioxide is taken in?
Cutting down trees means that less carbon dioxide is removed from the atmosphere during photosynthesis
What is biodiversity?
It is when a variety of different species live in a habitat, the more species the greater the biodiversity
Why does deforestation mean less diversity?
When rain forests are cut down habitats of huge number of different species are lost, this causes many species of become extinct and so biodiversity is reduced
Why is less biodiversity bad?
There are lots of useful products in the rainforest that we will probably never know about because the organism that produced them has become extinct, reducing our opportunities
What are bogs?
Areas of land that are acidic and waterlogged
Why does peat form in bogs?
Plants that live in bogs don’t fully decay because there isn’t enough oxygen, these partially rotted plants gradually build up to form peat
What happens to the carbon when a plant that lives in a bog decays?
Because the plants have only partially decayed to form peat there is some carbon stored in the peat
What are three reasons why peat bogs are often drained?
- ) so that the area can be used as farm land
- ) the peat can be cut up and dried to use as fuel
- ) it is used as compost
Why does destroying peat bogs add to the amount of carbon dioxide in the atmosphere?
As peat contains carbon as the bog is drained the peat starts to decompose releasing carbon dioxide
What is one way that people can help reduce the amount of peat bogs being drained?
Buy peat free compost to reduce the demand for peat