POPULATION and RESOURCES
31/10/14
LEARNING OBJECTIVES
1) Examine the concepts of optimum population,
overpopulation, under population and carrying
capacity
2) Examine the factors that influence changes in
carrying capacity
3) Explore the theories on the relationship between
population and resources
THE CONTEXT
• All development is for the people
• People are the ultimate and the only beneficiaries.
• Development is directed towards meeting the needs the
people.
• Development also contributes to capacity building of
individuals as well as group of individuals –family, society, etc.
• Development needs of the people are not the same.
• They vary by basic characteristics of population
– Size, Age, Sex
• The population stock determines the development needs.
• Development modifies the population stock through changes
in mortality, fertility and other determinants.
3
POPULATION AND RESOURCES
This PPT has been adapted from: http://www.slideshare.net/ecumene/population-9-intro-to-population-and-resources-presentation
CONTRASTING PLACES
Bangladesh population density =
981 people/km2
Sudan population density =
15.6 people/km2
Which one is over populated?
CONTRASTING PLACES
Amsterdam (the Netherlands, population
density = 397 people/km2)
Calcutta (India, population
density = 330 people/km2)
Which one is over populated?
RESOURCES - KEY CONCEPTS
1. Natural resources: environmental: mineral and
fossil resources. (i.e.: iron, oil)
2. Human resources: cultural, economic, technological
resources
3. Non-renewable resources: finite natural resources
(oil, coal, gas), capital (machinery, equipment)
4. Renewable resources: non-finite natural resources:
hydro power, wind, solar.
5. Reserves: Many countries hold “emergency”
reserves of finite resources (oil, grain, gas)
DEFINITIONS
1.
Over-population – when there are too many people and
not enough resources to provide a high standard of living
at a given level of technology.
2.
Under-population – when there are not enough people to
fully exploit the available resources.
3.
Optimum population – is the theoretical number of people
which, when working with all the available resources, will
produce the highest standard of living and quality of life
4.
Carrying capacity – the number of people that can be
supported by the available resources within a particular
area without the long-term depletion of those resources.
Population and
Resources
Theories on the relationship between
population and resources
Under-Population
Over-Population
Optimum Population

Benefits
Population
Impact
Problems

Population Growth over Time

THOMAS MALTHUS
• 1766-1834. Born in UK.
• Wrote ‘An essay on the Principle
of population’.
Published in 1798
• World pop. in 1798: 9 million people.
• Now: more than 6 billion
Malthus recognised that population - if
unchecked - grows at a geometric rate:
1
2
4
8
16
32
However, food only increases at an
arithmetic rate, as land is finite.
1 2 3 4 5 6
Thomas Malthus : Essay on the
Principles of Population 1798
Malthus was the first to notice the
impending issue of there being
more people than could be
supported by the food supply.
He noticed farming improvements
could raise food production by a
certain amount each year – in an
arithmetic rate of increase..1, 2, 3,
4, 5, 6…… Whereas population
tends to increase at a ‘geometric
rate’ with each generation…1, 2,
4, 8, 16, 32……. So he concluded
there must come a point when
there are too many people for the
available food supply
Therefore….
Malthusian Catastrophe
food
population
TIME
War,
famine,
disease.
Malthus believed that when the
population level rose above the food
supply – then nature would cause it
to decline due to:
PESTILENCE
PLAGUE
FAMINE
WAR
Malthus suggested that population growth
should be limited by people marrying later –
and abstaining from sex before and outside of
marriage. (he basically wanted to cut the birth
rate of the poorer classes)
These were very radical things for a vicar to
say!!
The Core Principles of Malthus:
• Food is necessary for human existence
• Human population grows faster than the power
of the earth to produce food.
• The effects of these two unequal powers must
be kept equal.
• Since humans tend not to limit their population
size voluntarily - “preventive checks” are
needed. (in Malthus’ terminology)
To check = to stop or slow
the progress of some
unwelcome process. to halt,
to stop, to slow something
down.
NEGATIVE CHECKS
(DECREASED BIRTH RATE)….
• Negative Checks: limit pop. growth by
decreasing birth rate: Examples: abstinence /
delay of marriage.
• (Malthus favoured moral restraint as a check on population
growth.
• However, it is worth noting that Malthus proposed this only
for the working and poor classes!)
POSITIVE CHECKS
(INCREASED DEATH RATE)
• Positive Checks: events which increase the
death rate such as famine, disease, war 
increasing the mortality rate and reducing life
expectancy.
If a population rises above
the ‘carrying capacity’ of an
environment – it will
struggle to survive. There is
much debate about what
the carrying capacity of
Planet Earth is.
The ‘carrying capacity’ is the potential of
an area to support life long-term. The area
must be able to provide:
• Food and water
• Space for living and shelter
• Essential resources for life
• Able to absorb waste and pollution
Any change in the population or
resources in an environment will
change the carrying capacity. These
changes may be short term or long
term. If a population rises above the
carrying capacity of its environment,
it can cause the environment to
deteriorate so that it even less able to
sustain a population.
Factors influencing carrying capacity
include:
1) Population Size
2) Environmental Resistance
3) Resource Innovation
Desertification on the margins of the Sahara
due to deforestation, over-cultivation of the
soil and over-grazing of grasslands means
that fewer people can be fed now in many
regions than 30 years ago – the carrying
capacity has been reduced.
Was Malthus right?
• ... There has been a population explosion
• ... Demand for food is rising rapidly
• ... Africa – repeated famines, wars, food
crisis, environmental degradation, soil
erosion, crop failure and disastrous floods –
so was he right?
But…..
• Technological improvements which he could
not have foreseen
• More farmland due to irrigation & better
technology
• Reduced population growth as countries move
through the DTM
The Demographic transition model (DTM) is a model used to represent the transition from high birth and death rates to low birth and death rates as a
country develops from a pre-industrial to an industrialized economic system. The theory was developed in 1929 by the American demographer Warren
Thompson.
'J' Curve - Population Crash Model
This follows the ideas
of Malthus:
population rapidly
expands, reaching the
carrying capacity of
the land. As the
population exceeds
this, famine and
disease play havoc
with the population
and it crashes.
Where do famine etc.
fit?
‘S' Curve - Stabilisation Model
This follows ideas of the
demographic transition
model over time.
A low base population is
followed by a rapidly
expanding one that
finally stabilizes at a new
high population level.
Neo-Malthusians would say that the
frequent famines in Ethiopia and
Sudan are evidence of Malthus’ basic
theories being right ….too many
people out-weighing the available
food resources
….but how come Britain never had
the ‘famine’ that Malthus predicted
– and we now suffer from too
much food with an obesity
epidemic?
Whilst Malthus’ prediction for Britain
were not to come about in his lifetime,
by the 1970s demographers felt there
was no putting off his predictions any
longer. The Club of Rome was a
gathering of scientists who said in
1972 that unless the population of the
earth was restricted by population
control policies, then humanity faced a
disastrous future with food shortages a
certainty within 100 years. These
theorists are known as NeoMalthusians (‘new Malthusians’ –
using his ideas)
Their book ‘Limits to Growth’ is the
best selling book on the environment –
ever.
Ester Boserup 1965
• Boserup believed that people have resources
of knowledge and technology and that
“necessity is the mother of invention”, thus as
populations grow towards the carrying
capacity, people develop new ways to use
resources (food) more productively.
• Can you think of real life examples?
Esther Boserup (1965) : The belief in human ingenuity to
come up with solutions at times of crisis.
This theorist claimed that rising populations
are not a problem. In fact, Boserup suggested
that it was at times when there were food
shortages following periods of population
growth, that people were forced to come up
with better ways of producing food in order to
survive. Summed up best by the phrase :
Necessity is the mother of invention.
Thus…….
• Demographic pressure (population density)
promotes innovation and higher productivity
in use of land (irrigation, weeding, crop
intensification, better seeds) and labour
(tools, better techniques).
Whose view on population growth
is this?
Ester Boserup
Whose view on population growth
is this?
Malthus
But….
• Boserup admits overpopulation can lead to
unsuitable farming practices which may degrade the
land
• population pressure as one of the reasons for
desertification in the Sahal region (so fragile
environments at risk)
• Potential consequences of Green Revolution
Was Boserup Right?
What about resource degradation and
pollution? Can we continue to innovate to
overcome these issues?
When Mao-Zedong, the Chinese leader
was asked in the 1960s how the country
could cope with the increasing number
of mouths to feed, he replied….
“With every stomach….comes a pair
of hands ! “
His priorities for China were:
Defence – building a big army
Industrialisation – to modernise China
He saw ‘more people’ as the best way
to achieve both these.
Population Policies : Managing Population and Resources
Carrying Capacity : The ability of an area to ‘support’ its population
by providing the essentials of life – food, water, living space, waste
disposal. As countries develop they move away from being SelfSufficient in food (and possibly water) and resources – and develop
Wealth-Creating Industry (factories, banking or tourism) to be able to
import the food and resources they need. This is why the UK didn’t
have the famines that Malthus predicted in the 1790s.
See BBC report on Optimum
Population Trust
Overpopulation : When the people in the country would be better off
if there were fewer of them. There may be insufficient food, water,
resources or living space. Policies may aim to encourage people to
emigrate, prevent immigration, and encourage people to have fewer
children. E.g China
Underpopulation : When the people in the country would be better
off if there were more of them. More people to exploit the country’s
resources, be consumers for industry, pay taxes and give
political/military strength e.g Australia, Canada, Brazil.
Optimum Population : Where the population size is ‘just right’ for
the resources available to the country. It’s very difficult to know what
a country’s ‘optimum is. Some people argue that the UK would be
better if it only had 35m people (on environmental grounds) whereas
other suggest we could compete better with Germany and Japan if
we had 80m (on economic grounds)
Population Policies : Historical Evidence of when Population gets out of balance
with Resources
Easter Island :
• Isolated island in the Pacific
• Evidence of a thriving culture in the 1600s-1700s
• Population grew, cultivated more land and thrived.
• By 1800 the population had declined considerably and was in a
state of poor diet, poor health and much deprivation.
• It is believed that as the population grew, more land was
cleared of forest for farmland.
• As all the land was used up, the soil was over-used and then
exhausted.
• Deforestation caused soil erosion and reduced the food
production
• As resources declined, tribal groups went to war with each
other for scarce resources
• The loss of trees meant no more boats could be built to allow
people to escape the islands.
• By the 1800s the population was declining through warfare,
inadequate food, and deteriorating soil conditions. Malthus’s
theory exactly.
Population Policies : Modern Evidence of when Population gets out of balance
with Resources
Mauritius :
•
Isolated island in the Indian ocean
•
Population was growing rapidly in the 1950s leading to overcultivation
•
The island was rapidly approaching over-population
•
The government and religious faiths came together to.,,,
a)
Reduce the population growth rate by introducing contraceptives.
The fertility rate fell from 4.2 to 2.8 in a decade as women embraced
the opportunity to limit the number of children they gave birth to
b)
Increase the food production of the island by (i) de-rocking the fields
to increase the land that could be cultivated (ii) dual-cropping –
growing bush/tree crops in strips alongside food crops. The taller
trees shade the lower ones and stop the soil drying out.
c)
The island moved away from trying to be self-sufficient in food, and
encouraged foreign firms to relocate there – making use of the
island’s well-educated workforce and low tax rates. The money
raised from taxes on the businesses has been used to import food.
•
Evaluation : by reducing population growth, increasing food
production, and increasing wealth to import food from abroad,
Mauritius used its creativity and ingenuity to prevent the island
getting out of balance with its resources. Boserup’s theory, with a bit
of Malthus too (the ‘reducing the population’ bit)
Anti-Natalist Policies : Reducing the Birth Rate
Theory : Neo-Malthusians
Belief : Population is growing faster and the world is
running out of finite resources. Unless governments limit
the growth of their populations, the world will face a
crisis of resource-shortage leading to conflict and war
Evidence : Oil wars (Iraq invading Kuwait 1990). USA
invading Iraq (1991 and 2001). Water conflict between
Israel and Palestine. Easter Island – 1800s.
Policy : Reduce Birth Rates by introducing free
contraception, improving education of poor women,
encouraging people to have fewer children
Examples : Mauritius, China.
Use this link for the s-cool
website revision guide on
Malthus
Use this link for a BBC
report on the one-child
policy
And this one….check the
dates on them both
Pro-Natalist Policies : Increasing the Birth Rate
Theory : Boserup
Belief : Population is a country’s greatest asset. People
can work, are productive, and can be inventive. The
more people you have, the more workers, the greater
the number of consumers for industrial goods, the more
taxes can be paid, the more trade can take place.
Evidence : When countries face starvation – it’s usually
due to civil war or climate change – not too many
people to feed. As the world’s population has grown –
there have been fewer famines – not more. The most
successful economies of the 21st century are the ones
with larger populations (USA, China, Brazil, India, UK,
Germany..)
Policy : Increase Birth Rates by introducing incentives
for women to have more children (paid maternity leave,
free child-care, increased child-allowance for 3rd child).
Or increase immigration by encouraging new settlers.
Examples : Under-populated countries with large land
areas and sparse population – Canada, Australia,
Brazil, New Zealand. Countries in Stage 5 of the DTM
with increasing elderly populations and few young
people – Japan, Sweden, France, Italy, Germany.
French government eyes 'le baby boom' In the latest in
our series about motherhood and the role of the state in
encouraging couples to have more children, Hugh
Schofield in Paris reflects on efforts made by successive
French governments to ensure women give birth to more
and more children.
When people ask why I decided to settle in France six years
ago, one of my answers is that it is easier to bring up a
family here. Because it's true.
The Schofields - the more children you have, the less
income tax you pay
On the purely financial side, there are several ways in
which government policy helps those of us who choose to
breed. The most important of these is a calibrated incometax rate which means that the more children you have, the
less you pay.
See the rest of this BBC
report on France’s pronatalist policy
And this BBC report on
Japan’s problems of an
ageing population
…and what the Japanese
women are being told to do
about it!
Pro-Natalist Policies in
Stage 5 countries with
Ageing populations.
Activity
Due – 04/11/14
‘Population growth leads to development’.
a) State 3 main features of Boserup’s view of the relationship
between resources and population growth.
b) Outline ONE criticism of this theory