Pollution

1
Pollution
2
Pollution

• There are three types of pollution
• Land
• Water
• Air
• All of these affect living things by destroying
  habitats and disrupting food webs

3
Land Pollution

• Landfill sites lead to water being contaminated
• Household waste should be recycled
• Deforestation leads to deserts as the ground can
  hold less water

4
Landfill Sites
5
Water Pollution

• This is caused by
• Acid Rain (which kills leaves and builds up in
  rivers, lakes and streams to kill fish)
• Oil Spills (killing birds and fish, as well as
  destroying beach habitats)
• Sewage (warm water carries less Oxygen)
• Algal booms (fertilisers leaching into rivers,
  lakes and streams)

6
Acid Rain Kills Plants
7
Acid Rain Destroys Monuments
8
Oil Spills Kill Wildlife
9
Raw Sewage
10
Warm Water from Factories

• Warm water holds less Oxygen
• This means that fish and aquatic animals will
  suffer and possibly die

11
Cholera

• Cholera is caused by a type of bacteria
• It was found in contaminated water throughout the
  19th Century
• Victims suffer from severe diarrhoea, which leads
  to death

12
Algae Blooms
13
Air Pollution

• This includes
• Smog (a man made fog)
• Acid rain (caused by Carbon Dioxide, Sulphur
  Dioxide and Nitrogen Oxide coming from exhaust
  fumes)
• The Greenhouse effect caused by Carbon Dioxide
• Cigarette smoke (which can cause cancer)

14
Waste Incineration

• This plant in Sweden can burn up to 25 tonnes of
  waste per hour

15
Smog

• This is a man made fog

16
Smog In Beijing

• Left A Sunny Day Right It had rained
  for 2 Days

17
Global Warming

• This is caused by the greenhouse effect
• Carbon Dioxide and Methane produced by burning
  (combustion) traps heat in the Earths atmosphere
• This trapped heat raises the temperature of the
  Earth
• The major danger is the polar ice caps melting
  raising the water level
• Or that the temperature will spin out of control
  and send us into a severe ice age

18
(No Transcript)
19
(No Transcript)
20
The Greenhouse Effect

• This is when the atmosphere traps heat from the
  Sun keeping the Earth warm
• The Earth reflects 30 of the suns heat
• 70 is absorbed, some of which can escape
• The main gases that increase the trapped heat
  are
• Methane (produced by microbes and cows burping)
• Carbon Dioxide (from combustion)
• Water vapour (clouds)
• Ozone and CFCs

21
(No Transcript)
22
Recycling

• Re-using useful materials
• As well as reducing the amount of waste produced
  by people (each house produces 1 tonne of rubbish
  per year or 31 million tonnes for the UK source
  Waste Watch
• It costs 1.6 billion per year to manage waste
  Source Waste not, Want not Cabinet Office,
  2002
• The main recyclables are
• Aluminium
• Glass
• Paper
• Steel/ Iron
• Textiles
• Asphalt

23
Facts

• Just one recycled aluminium can saves enough
  energy to run a television set for three hours!
  sourcewww.alupro.org.uk
• Every steel can is 100 recyclable. It can be
  recycled over and over again into products like
  bicycles and of course new cans source
  www.recycle-more.co.uk 
• Glass can be recycled again and again without
  losing its clarity or purity source
  www.britglass.co.uk 
• One bottle bank can hold up to 3,000 bottles
  before it needs to be emptied. source
  www.britglass.co.uk 

24
Facts

• Making glass bottles and jars from recycled ones
  saves energy. The energy saving from recycling
  one bottle will - Power a 100 watt light bulb
  for almost an hour - Power a computer for 20
  minutes - Power a colour TV for 15 minutes -
  Power a washing machine for 10 minutes source
  www.britglass.co.uk 
• 13 billion (13,000,000,000) plastic carrier bags
  are used in the UK each year. source Defra

25
Biodegradable or Not?

• Anything that has come from a living things
  decomposes
• Plastics are not biodegradable
• Biodegradable materials are broken down by
  bacteria and fungi
• These can be used to produce methane from the
  materials in your brown bin

26
(No Transcript)
27
Decomposers

• Bacteria and fungi that break down dead organisms

This peach is decaying over 6 days due to mould
(fungi)
28
Food Spoilage

• Bread goes mouldy
• This is caused by fungi and fungal spores

29
Microbes

• Some microbes decompose food
• They need Oxygen and water to survive
• Foods can be preserved by cooling the bacteria or
  preventing them from getting Oxygen or water

30
Bacteria Reproducing
31
Preserving Food

• Food starts to decay after a short period of time
• This spoilage makes it unattractive and taste
  different
• Decay is caused by bacteria on the food of fungal
  spores

32
Refrigeration

• Low temperatures slow down the growth of bacteria
  and fungi
• Freezing stops bacteria and fungi due to low
  temperatures and the fact they need water (which
  is frozen)

33
Drying/ Adding Salt

• This takes water away from the food
• Bacteria and fungi need water to grow and
  reproduce
• Meat like pork is usually dried by adding salt
• Raisins are dried grapes

34
Pickling

• Onions and beetroot can be pickled
• These are stored in acid, usually vinegar
• Eggs can be pickled

35
Canning and Bottling

• Cooked fruit or vegetables are placed in sterile
  cans or jars
• They are then boiled to destroy any bacteria
  inside them
• These foods spoil once the can is opened

36
Pasteurisation

• Named after Louis Pasteur
• Milk is heated to destroy bacteria that make it
  sour
• Batch pasteurisation heated the milk to 68
  Celsius for 30 minutes
• HT pasteurisation involves heating milk to
  71Celsius for 10 to 15 seconds
• This kills most of the bacteria, but not all
• UHT is heated to 138 Celsius for a fraction of a
  second
• UHT and sterilized milk kills all microbes and
  can be kept for months, until opened
• The main problem with heating milk to a high
  temperature is that it can affect the taste

37
UHT Milk
38
Invasive Species

• This plant was native to Japan, but introduced
  into Britain

39
Squirrels

• Red squirrels are native to Britain, but when the
  Gray squirrel was introduced the red version
  began to die out