Transcript Environmental Issues

Environmental
Issues
This topic will be
examined, through
source and recall
questions, in Paper 1
of the GCSE.
It links with
knowledge gained in
Science classes.
 THE ENVIRONMENT
 Simply, the environment is our
surroundings. It :
 has taken billions of years to evolve
 may be natural or managed
 is a huge ecosystem made up of
other sub - systems
 can be tiny (microsystems), local,
national, global or universal in scale
 is fragile and very easily damaged
 is inter – connected and self reliant
 is the source of EVERYTHING
mankind needs
 An ecosystem is a natural system whose
members benefit from each other's
participation via symbiotic relationships. It
is a term that originated from biology, and
refers to self-sustaining life systems
Competition
Any living species competes with each other. They may
compete for:
- Living space
- Food
- Water
Get off my
land, you tiny
little double
humper!
- Mates
In addition to this competition, the population of a species can
be affected by predators, disease, migration and other factors.
Yum! Marmot
Surprise!
Predators and Prey
A PREDATOR is an animal that hunts and eats another
animal
The PREY is the animal it eats, for example
Prey
How
tiresome.
Bunny again!
Predator
Consider the populations of these two animals over time:
Population
of animal
Rabbit
Fox
Time
Food Chains
A food chain shows where the energy goes in a food chain
(in other words, “what gets eaten by what”):
Cabbage
Rabbit
Plants convert the Sun’s
energy into food
Stoat
Fox
The arrows indicate where the
energy is going
Pyramids of Biomass
In this food chain we can see that the mass of organisms
in each stage is less than in the previous stage:
Cabbage
Rabbit
Stoat
Fox
We can draw a “Pyramid of Biomass” to show this pattern:
Mass of foxes
Mass of stoats
Mass of rabbits
Mass of cabbages
Improving the efficiency of a food
chain
Clearly, food chains aren’t very efficient. How could the
efficiency of a food chain be improved?
1) Reduce the number of stages in the chain:
Cabbage
Rabbit
Stoat
2) Limit an animal’s movement
or keep it warm
3) Use plant hormones to regulate the
ripening of fruit
Fox
Recycling ourselves
Microbes are the key to this – they break down waste and
dead bodies so that the products can be used by plants for
growth. Microbes work best in warm, moist conditions where
there is plenty of oxygen.
The Carbon Cycle
6. These
microbes also
release CO2
through
respiration
CO2 in air
1. CO2 is taken in by
plants for
photosynthesis and
turned into
carbohydrates
4. Animals
release CO2
through
respiration
5. Animals (and
plants) die and their
remains are fed on
by microbes
2. Plants release
CO2 through
respiration
3. The carbon is
taken in by plants
is then eaten by
animals
The Nitrogen Cycle
4. Nitrifying bacteria convert
ammonium compounds into
NITRATES
Waste and
dead animals
1. Plants absorb nitrogen
in the form of NITRATES
Nitrates in
the soil
Plants
Animals
3. Microbes break down
waste products and dead
animals and plants to form
AMMONIUM COMPOUNDS
2. Plants are then eaten
by animals – the
nitrogen becomes
PROTEIN
Why are there
environmental issues?
 A massive increase in world
population. By 2050 the world
population is expected to be 9
billion. Over 75 million people are
added to the world each year.
 A lot more technology is used in
every day life. This means natural
resources are used increasingly.
 Desires and expectations have
changed.
 Although we are
multicultural, many people
in MEDCs are “out of touch”
with their environments.
MEDC lifestyle is often
divorced from direct
environmental contact.
 Our attitudes often swing
from irrational fears to lack
of care or concern.
 Like all our attitudes, our
attitude to the environment
is culturally socialised.
KEY IDEA 1
Culture and beliefs
influence the ways in
which individuals,
groups and societies
perceive and exploit
natural resources
terminology, ecosystems, issues, cultural comparisons
KEY IDEA 2
Problems can arise
from the different
ways in which
people want to use
the environment
atmospheric pollution and deforestation: what, why, how and who, plus
alternatives and models for sustainability
KEY IDEA 3
Environmental
issues have
varying effects
on individuals,
groups and
societies
tourism and the environment, LEDC (and maybe MEDC) case studies
KEY IDEA 4
Individuals, groups and
societies can play an
important part in
influencing behaviour,
attitudes and values
regarding environmental
issues
case study of pressure groups, their methods and effectiveness
The Rainforest
 Deforestation: cutting down
trees.
 2 football pitches disappear a
second.
 One third have been
destroyed.
 Considered very importanthalf the worlds species of
plant/animal live there.
 a cure for aids?
Case Study- Brazilian
Rainforest
 What is happening????
 Deforestation- trees converted into
timber for sale abroad. Particular
demand for hardwoods such as
mahogany.
 Minerals are extracted from the land
beneath the trees. E.g. iron ore,
diamonds
Causes
 Clearance of rainforest provides plots of land for
rapidly growing populations.
 Cattle ranching- land often used for 2 years only
before worn out and nutrient empty.
 Engineering projects- eg dams, roads, settlements.
Territory is opened up, electricity gained.
Groups Involved
 Scientists and
researchers
 Brazilian government
 Commercial companies
e.g. loggers
 Original inhabitants of the
forest.
 Growing population of
poor people from the
surrounding countryside.
Effects
 Desertification- if trees are
removed, less water is
held, rainfall decreases,
the area becomes drier.
 Soil erosion- exposure
means it is washed away
by heavy rain.
 Global warming – trees no
longer absorb CO2 so it is
released into the
atmosphere.
 Animals, insects, plants
die. New medicines are
disappearing?
What Can be Done?
 Stewardship – understand the
needs of the environment and
treat it appropriately.
 Sustainable development – meet
the needs of the present without
compromising the future.
 Protect and manage the
remaining forests
 Improve quality of life for
people through other
means.
 Agreement from
governments and groups
to conserve the forest.
Natural Resource
Exploitation
 ‘Exploit’- what does it mean?
Case Study – Aral Sea
 Once the 4th biggest
inland sea in the world.
 1960s – flow of water
dropped – the Soviet
government had set up
a major irrigation
scheme in order to grow
lots of rice and cotton to
help the Russian
economy.
 90% + of natural flow
was diverted.
 Sea level fell 14 m.
Water was twice as
salty.
Effects
 Climate – winters are colder and
summers are hotter as the sea
water no longer moderates.
Rainfall has declined.
 Desertification- salt in the air.
Toxic dust.
 Work – cotton and rice industries
are failing. Harbours are inland!
Fish die.
 Water Supply – short
supply/polluted.
 Health- no water, salty/dusty air.
Endangered Species
Case Study – Fish and Marine
Life
 Demand for fish has
increased. (10 fold since
1970 in Asia)
 Total world sea fish catch
has increased steadily
since 1950
 The world’s fish stock has
almost been fully
exploited.
 (this means dropped to
levels where species might
die out)
 Fishing has changed since 1950.
 Bigger nets
 Huge factory ships
 Fish detected with greater accuracy- electronic.
 Catch young fish as well now- not yet bred.
 By-catch- needless killing of ‘non target’ species.
Kills not only fish, but porpoises, dolphins etc
What can be done?
 Regulation of industry
 International laws
 UN Convention on the Law of the Seas.
A Striped Bass from the
Atlantic Ocean
 Problems though…….
 Oceans are huge!
 Countries regard their coastal
waters as their territory under their
control.
 Oceans are international- no clear
responsibility.
 Growing populations and growing
wealth- demand is rising.
 Fishermen have to be honest
about quotas.
Pollution
 Any substance in water, soil or air which
damages the natural environment. It
may offend people’s sight, taste, hearing,
or smell, and/or cause a health hazard.
The usefulness of a natural resource is
usually reduced by being polluted.
Case Study - Oceans
 ‘’The solution to pollution is dilution’’
 Treated like an open sewer.
 Bags, netting, packaging, human sewage,
factory outflows of acids, poisonous metals,
farm chemicals, nuclear waste, oil.
 Many countries have no other affordable
way to dispose
 of sewage and
 other waste.
Effects
 Agricultural – waste contains nutrients from fertilisers.
Excessive amounts makes algae grow which kills other
marine life. (called red, brown or green tides).
 Sewage – kills living things. Surfers are at risk from toxic
spray.
 Oil spills/discharges – ships pump out toxic waste
(ballast).
 Chemicals/air borne gases and particles – new chemicals
such as DDTA or PCBs end up in the fat of sea life such
as bears, seals, whales, sharks. They affect hormones
and therefore breeding.
 Other dumped waste – plastic doesn’t disintegrate easily.
The Yangtze Dolphin in the Yangtze River
Salmon in the River Thames
Are There Solutions?
 You need to change people’s perceptions that the
oceans can clean the world.
 Lack of wealth and resources restricts improvement.
 Redesign and replacement of better sewage systems
is not popular.
 Other waste disposal methods would bankrupt
industries and companies.
 The seas are too large to police. There is open
access. Pollution can move!
 Growing populations and increased pressure.
Action:
 Governments – monitor areas and control
dumping. Polluters can be fined. Can lead
protests about international problems.
 Environmental groups – can protest to prevent
pollution. They help arouse public interest.
E.g. Surfers against Sewage in Cornwall.
 UN – laws / fines
Sustainable Exploitation.
 Non renewable resources
 What are they?
 Examples?
Natural Gas
 Wood
 Widely used in LEDCs as fuel.
 Technically a renewable resource but large trees
are being cut down more quickly than they can
be replaced.
 Fossil Fuels
 Take ages to be created
 Oil and gas are almost used up.
 Coal is running out
 Will we run out in 60 years time????
 What has happened to demands?
Fossil fuels cause
pollution.
 On burning they produce carbon dioxide,
sulphur oxides and nitrogen oxides.
 These lead to :
CLIMATE CHANGE
ACID RAIN
SMOG
In Mexico City, ¼ of all fruit and vegetables
grown are contaminated with deadly
levels toxic pollutants.
Nuclear Power
 28% of UK power
 Chernobyl
 Difficult and expensive
to dispose of
nuclear waste.
Renewable Energy
Sources
What are the benefits and problems with each?
 Hydropower (think about the Three Gorges
Dam – 1.2 million people displaced)
 Wave Power
 Tidal Power
 Solar Energy
 Wind Energy
 Bioenergy
The Impact of Leisure and
Tourism
 Tourism is big business. (8% of total
world trade, involves 10% of the U.K
population, gives Caribbean islands 50%
of their income)
 Tourism is growing and changing rapidly.
How is it an environmental
issue? The Effects
 Transport
 Accommodation / Use of local resources.
 Leisure Activities and Changes in Land
Use– there were almost 2000 ascents of
Everest in 2003.
 Changes in local lifestyles
New cultures replace the old.
Controlling the Effects
 Local community groups e.g. the Himalayan Code for Tourism in
Nepal.
 Independent organisations / pressure groups - e.g WWF
contribute funds to projects.
 The travel industry – eco-travel associations set up. ‘’Green
Globe’’
SUSTAINABLE TOURISM
ECO TOURISM
Climate Change
 More and more greenhouse gases in
the atmosphere act like a blanket,
trapping heat.
 An increase in global temperatures.
 Guaranteed to happen in YOUR
lifetime.
 Will drastically change weather
patterns
 This will in turn affect plants/animals.
 Are the changes part of century long
patterns? Yes and no……..
Most agree climate
change IS occurring……
 Increasing CO2
 Evidence of changes in climate
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Glaciers are melting
Low lying coastal areas are disappearing
Record heat waves eg May, 2003, India, 49°C
An increase in the number of serious droughts
Heavier rainfall and increased flooding in Bangladesh
Insects and diseases are migrating. Malaria in the
U.K?
Why is Climate Change a
Problem?
 Unpredictable effects
 Effects on plant and animal life
 Uneven impact across the world
 The wet get wetter, the dry get drier.
Solutions
 Reduce the greenhouse gases produced.
 The Kyoto Protocols (1997) – countries agree levels of
acceptable emissions. There are goals to reduce
outputs. The USA is a key problem.
 The U.K government is cutting down on coal burning,
and encouraging cleaner energy production.
 Individuals – use less energy, use public transport,
recycle.
 Accept it will happen and prepare to
adapt.
 Extreme weather- prepare, predict, protect!
What can we do about
environmental problems?
 Identify the issue
 Work out what can be done
 Persuade people to take action
Government
 Local Agenda 21 – local authorities
encourage local partnerships between
communities, businesses, and
themselves. This includes recycling and
traffic reduction.
 Stopped the sale of leaded petrol
 Inspections of industrial sites
 Educates the public.
Pressure Groups
 Union of Concerned
Scientists- produce
publications full of scientific
data.
 Friends of the Earthcampaign, advertise, collect
funds, produce materials for
schools, demonstrate,
appear in the media.
 Greenpeace – campaign!
Spectacular publicity!
Ordinary People
 Local single interest groups – campaign
locally.
 Individuals – burn less fossil fuels, use
cars less, recycle, produce less waste,
buy ‘environmentally friendly’ goods, use
alternative energy sources.
To Conclude……
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Think through all the ideas covered.
Focus on CAUSE and EFFECT
Know your case studies.
Mind map key ideas for each sub topic.
Remember the tips from the last session.
Have you taken anything from this
material? I hope so.