Upload
marl-pua
View
235
Download
0
Tags:
Embed Size (px)
DESCRIPTION
geog
Citation preview
Population Geography
Distribution of World Population
Rates of Population Growth
Demographic Transition Theory
Overpopulation (Malthus and Neo-Malthusians
The first hominids roamed eastern Africa
5-7 million years ago.
Humanity has wandered the
earth for a very long time.
The first modern humans walked
out of Africa as hunter-gatherers
only 70,000 years ago.
Graph Source: www.census.gov & www.wikipedia.org
At that time there were probably
about 1 million humans on Earth
Graph Source: www.census.gov & www.wikipedia.org
When Darwin published On the Origin of
Species there were 1 billion humans
Graph Source: www.census.gov & www.wikipedia.org
When I was born there were
5.0 billion humans
The U.S. Census Bureau estimates the world
population at:
7.2 Billion humans today
…and counting!
http://www.worldometers.inf
o/world-population/
Our impacts
are growing.
LANDSAT
Images
1973 - 2006
Las
Vegas,
Nevada
Human Impact on The Environment
Source: Hugo Ahlenius. 2003. UNEP/GRID-Arendal. Global Environmental Outlook 3, 2002.
Human Impact on the Environment, 1700 Human Impact on the Environment, 2002 Human Impact on the Environment, 2032
Densely Population Areas
• East Asia
• South Asia
• Southeast Asia
• Europe
• North America
WHERE ARE THE PEOPLE
DISTRIBUTED?
Sparsely Population Areas
• arid lands
• tropical rainforests
• highlands
• high latitudes
World and Country Population Totals
Distribution and Structure: 3/4 of people live on 5% of earth's surface!
Total: 6.8 billion on planet as of March 5, 2010 Current World Population Counter from U.S Census Bureau
Five most populous regions and countries
REGION POPULATION COUNTRY POPULATION
East Asia 1.6 billion China 1.3 billion South Asia 1.5 billion India 1.1 billion Europe 1 billion U.S. 300 million SE Asia 600 million Indonesia 250 million Eastern N. America &
Canada 275 million Brazil 188 million
Kolkata, India
Rajasthan, India
Overpopulation is when there are too many people
relative to available resources. Simple density is not the determinant.
Human Population Projections How many people will the planet eventually support?
The U.S. Census Bureau and the United Nations Statistics Division both agree that world population will level off somewhere between 9 and 11 billion people and then start to fall.
Doubling Time • How long will it take for a population
of a given area to double in size?
• Divide 70 by the annual population
natural increase rate and you find the
doubling time.
World = 58 Sub-Saharan Africa = 30 Uganda = 20 years Costa Rica = 80 U.S.A. = 128 years Denmark = 333 years Russia = ? Japan = ?
Example: Bangladesh 70 / R.N.I. => 70/2.09 = 33.5 years
Bangladesh with a population of
144.3 million people in 2005 will
have approximately 288.6
million people in 2038, if the
population continues to grow at
current rates.
Source: National Geographic Magazine
Rates of Natural Increase
Total Fertility Rate
Palestinian Territories
Fertility Rate
1975-1980 7.39
1980-1985 7.00
1985-1990 6.43
1990-1995 6.46
1995-2000 5.99
2000-2005 5.57
2.1 is generally regarded as the replacement rate (the rate at which a population neither grows nor shrinks) in the developed world. In less developed countries this rate should be higher to account for so many children not reaching childbearing age.
Africa
Fertility Rate
1975-1980 6.60
1980-1985 6.45
1985-1990 6.11
1990-1995 5.67
1995-2000 5.26
2000-2005 4.97
U.K. Total
fertility rate
1975-1980 1.72
1980-1985 1.80
1985-1990 1.81
1990-1995 1.78
1995-2000 1.70
2000-2005 1.66
Total Fertility Rate - the average number of
children a women will have in her
childbearing years. This rate varies from just
over 1 (Japan, Italy) to around 7 (Niger, Mali).
The U.S. rate is 2.
Infant Mortality Rate – the number of deaths of children under the age
of one per thousand live births. The rate ranges from as low as 3
(Singapore, Iceland) to as much as 150 (Sierra Leone, Afghanistan). The
U.S. rate is just over 6. High infant mortality tends to result in higher
fertility rates as families seek “insurance” for the loss of children.
World Death Rates
Epidemiological Transition is the shift from infectious to degenerative diseases that occurs with development.
Infectious diseases (developing world) – HIV/AIDS
– SARS
– Malaria
– Cholera
Degenerative diseases (developed countries) – Obesity
– Tobacco use
Adults and Children Living with HIV/AIDS, mid-2006
Life Expectancy
Life Expectancy
Rapid increase throughout world
Infant mortality rate declining in most countries
Antibiotics/immunization
Increasing standards of living
Influences on Birth Rates Family planning
programs – India, Thailand, Bangladesh, etc.
Contraceptive technology
Role of mass media – Radio/TV Soap Operas
("Twende na Wakati" in 1990s Tanzania, which means "Let's Go with the Times"
Government Billboard, Indonesia
Demographic Transition Model
Stage one (preindustrial/pre-agricultural) – Crude birth/death rate high – Fragile, but stable, population
Stage two (improved agriculture and medicine) – Lower death rates – Infant mortality rate falls – Natural increase very high
Stage three (attitudes change) – Indicative of richer developed
countries – Higher standards of
living/education – Crude birth rate finally falls
Stage four (low growth or Z.P.G.) – Crude birth and death rates low – Population stable – Populations aging
Stage five (declining) – Crude birth rates exceptionally low – death rates low – Population decreasing – Populations aging rapidly
Problems with the Demographic Transition Model
• based on European experience, assumes all countries will progress to complete industrialization and that this is key issue
• many countries reducing growth rate dramatically without increase in wealth or industrial economies – TV and family planning seem to be at work
• on the other hand, some countries “stuck” in stage 2 or stage 3, particularly in Sub-Saharan Africa and Middle East
Most Populous Cities (2012)
Population Pyramids
Population Pyramids quickly show
• age distributions
• demographic booms and busts
• sex ratios
• dependency ratios
Wide base depicts young
population; narrow base suggests
declining birth rates or growing
elderly population.
Population Dynamics
Cartograms
A cartogram is a map in which a thematic mapping variable is used to represent the extent of a location instead of land area or distance.
Cartograms
Waldo Tobler (born 1930): Made the first computer-generated cartogram. American geographer and cartographer, Professor Emeritus at the University of California, Dep’t of Geography Famous for: "Everything is related to everything else, but near things are more related to each other"
Overpopulation
Definition and Some Important Issues
1. Population Control Thailand Success Story
Birth Control
2. Urbanization
3. Coastal Change
4. Population Impacts
Overpopulation When consumption of
natural resources by people outstrip the ability of a natural region to replace those natural resources.
When the carrying capacity of a natural region is reached
1. Urbanization
Definition
“Urbanization is a process of urban growth. It leads to a greater proportion of people being concentrated into towns and cities”
In 2008 – for the first time in history over 50% of the world’s population lived in towns and cities.
Urbanization – results in an increasing proportion of city dwellers in contrast to those in the countryside
Urbanization is a worldwide process – it began at different times in different parts of the world and occurred at contrasting paces.
Causes of urbanization
1. Rural to urban migration
2. Natural Increase
Structures and their impact to the beach profile
Breakwaters
Barriers
Sea Walls
Buildings and Houses
Coastal Change
Rapid increase in population, especially in developing countries, will lead to more coastal cities.
As coastal zones become more densely populated, coastal water quality will suffer, wildlife will be displaced, and shorelines will erode.
The appearance of coastlines and beach profiles will significantly change over time.
Population Control
Means of controlling or altering population growth rate and/or factors that can influence population size.
Population Control
Challenges
– Manufacture/distribution expense
– Religion
– Inequality of Sexes
– Preference for male children
– Female Infanticide
Thailand - an example of success
Annual population growth dropped from 3.3% in 1972 to 1.2% in 1995. This has been more or less the stable rate.
Community-Based Family Planning Service (CBFPS). Focused on wants and needs of poor.
How did Thailand Accomplish Demographic Transition?
• Breaking taboos of contraception
• Free contraceptives
• Financial incentives
• Reduced infant mortality due to infectious diseases - clean water supply
• Altered desired number of children (from 8 to 3)
Meanwhile, in China
• In China, population control is a political outcome • Women must receive “birth coupons” prior to
conception • Mass murders of girl babies • Abortions (even at 9 months gestation) • Women of reproductive age examined and
monitored
The Philippines: Learning from Thailand
• Dr. Nibhon Debavalya, Thailand’s leading population expert, responds with a parable about Thailand and the Philippines. (inquirer.net/9489/family-planning-in-
thailand-ph)
The Philippines: Learning from Thailand
Thailand was able to radically reduce its population growth rate to 0.6 percent while the Philippines inched down to 2.04 percent in the period 1970-2010. During the period 1970-2008, Thailand’s GDP per capita grew by 4.4 percent, while the Philippines’ grew by 1.4 percent. By 2008, Thailand’s total GDP was $273 billion while the Philippines’ was $167 billion.
Population Growth - Optimistic
Growing prosperity will reduce desire for large
families.
Technology/communication will spread
information faster, making transition more rapid
than it occurred for more developed countries.
Fertility rates are dropping and populations are
stabilizing (except in Africa).
Population Growth - Pessimistic Demographic trap:
poorer countries will
not become
developed enough for
birth rate to be
reduced, causing
population growth
rates to remain high.
Catastrophe will be
the only regulatory
control.
• predicted that innovation and the resulting increased wealth and choice it creates would provide alternate foods and resources in the future and lead to fewer children per family and improving societies: larger populations are good because they lead to more innovations and ideas.
• believed that society was perfectible
Jean Antoine Condorcet (1743 – 1794)
Thomas Malthus on Population
Malthus, responding to Condorcet, predicted population would outrun food supply - leading to a decrease in food/person
His Assumptions:
Populations grow geometrically.
Food supply grows arithmetically.
Food shortages and chaos inevitable.
An Essay on the Principle of Population, 1798
Food Population
2 2
4 4
8 16
16 256
Population J-Curve This graphs depicts the actual growth in human population
from the beginning of agriculture until 2000!
Population Impacts
Population and the Environment
To put these two in context, consider the following equation:
I = P x A x T where I = environmental impact P = the population size A = affluence (or consumption) T = effects of the technology used People overpopulation relates the first term - P Consumption overpopulation relates to the last two terms - A and T.
Population and the Environment
Population-influenced environmental problems:
• Global Warming
• Habitat Loss / Endangered Species
• Resource Depletion
• Food Shortages? Not globally, but regionally.
Population, Affluence, and Resource Consumption
Population, Affluence, and Resource Consumption
Source: World Bank, 2012: siteresources.worldbank.org/
Technology, Energy Consumption, and Environmental Impact
There has been a dramatic increase in:
• individual energy use over time: 3,000 kcal/person -
300,000 kcal/person (each of us in the U.S. has the equivalent of about 100 energy servants)
• the power of technology to change the environment: think stone axe versus bulldozer versus atomic bomb.
• the scope and severity of environmental impacts.
Individual Annual Energy Use (Goudie, 2006)