Title: Population
1Population
2Where do people live and why?Demography- the
study of population
- Demographers use concepts such as
- Population Density- measure of total population
relative to land size- also called
- Arithmetic Population Density- assumes even
density over the land - US is 79/sq mile
- Egypt is 73.3 million total pop, 190/sq mile
- Physiologic Population Density- total population
per unit area of arable (farmable) land - Does not count water/mountains/deserts where no
people live - Egypt- 6319/sq mile when measured like this
3Arithmetic Population Density
Fig. 2-4 Arithmetic population density is the
number of people per total land area. The
highest densities are found in parts of Asia and
Europe.
4Physiological Density
Fig. 2-5 Physiological density is the number of
people per arable land area. This is a good
measure of the relation between population and
agricultural resources in a society.
5Population Density Egypt
- All but 5 of Egyptian people live in the Nile
river valley - It is the only area in the country that receives
enough moisture to allow intensive cultivation of
crops
6Population Distribution-
- descriptions of the locations where people (or
groups) live - Dot maps provide a good representation of
distribution - People unevenly distributed across the globe
7World Population Cartogram
Fig. 2-1 This cartogram displays countries by
the size of their population rather than their
land area. (Only countries with 50 million or
more people are named.)
8World Population Distribution
Fig. 2-2 World population is very unevenly
distributed across the Earths surface and it can
be compared to climate distribution.
9Expansion of the Ecumene 5000 B.C.A.D. 1900
Fig. 2-3 The ecumene, or the portion of the
Earth with permanent human settlement, has
expanded to cover most of the worlds land area.
10Population Distribution
- Densely populated regions
- Low lands
- Fertile soil
- Temperate climate
- Sparsely Populated Regions
- dry lands
- wet lands
- high lands
- cold lands
11Major Population Clusters (p. 40-41)
- East Asia- Largest cluster (1.55 billion people)
- Contains China (1.3 billion), Korea and Japan
- South Asia- 2nd largest cluster (1.45 billion
people) - Contains India, Pakistan, Bangladesh, and Sri
Lanka - Bangladeshs pop density in the rural areas is
between 3000-5000 people per sq mile - Europe- 3rd largest cluster (728 mil)
- Population reflects coal fields and cities, not
farmland and rivers as in Asia - North America- 4th largest cluster (329.4
million) - Concentrated in N.E. US and S.E. Canada
- Reflects a megalopolis (overlapping urban areas)-
from Boston-Washington D.C.
12Reliability of Population data
- Census- count of the entire population of a
country, performed every 10 years in the US - Used to give government money for building
schools, parks, social services, etc. - Does not count homeless, minorities, and others
so they may not get funding for help - Us undercounted in 2000 by about 3.3 million,
what about less well off countries??? - Other agencies also gather data on world
populations - World Bank
- United Nations
- Population Reference Bureau
- Each has inconsistencies in their statistics
13Why do Populations Rise or Fall in Particular
Places?
- In 1960 Paul Ehrlich published Population Bomb,
in which he warned that the worlds population
was increasing too quickly and was outpacing our
food production - Thomas Malthus- wrote An Essay on the Principles
of Population - population was increasing faster than food
production - Said that food grew linearly while population
grew exponentially - Was wrong, because he did not predict that
mercantilism, colonialism, and globalization
would bring the world in closer contact and
spread crops and farming methods - Neo-Malthusians- followers of Malthus today that
dont believe every detail, but are concerned
with population growth and feeding the world
14Food and Population, 19502000Malthus vs. Actual
Trends
Fig. 2-20 Malthus predicted population would
grow faster than food production, but food
production actually expanded faster than
population in the second half of the twentieth
century.
15Population Growth at Different Scales
- Terms concerned with population growth
- Rate of Natural Increase- births minus deaths
over a period of time (year) - CBR (crude birth rate)- of live births per
year per thousand people in a population - CDR (crude death rate)- of deaths per year per
thousand people
16Crude Birth Rates
Fig. 2-8 The crude birth rate (CBR) is the total
number of births in a country per 1,000
population per year. The lowest rates are in
Europe, and the highest rates are in Africa and
several Asian countries.
17Crude Death Rates
Fig. 2-12 The crude death rate (CDR) is the
total number of deaths in a country per 1,000
population per year. Because wealthy countries
are in a late stage of the demographic
transition, they often have a higher CDR than
poorer countries.
18Natural Increase Rates
Fig. 2-7 The natural increase rate (NIR) is the
percentage growth or decline in the population of
a country per year (not including net migration).
Countries in Africa and Southwest Asia have the
highest current rates, while Russia and some
European countries have negative rates.
19Terms, cont.
- Demographic Change- Measured with a formula
- B-DI-E (births deathsimmigration-emigration)
- TFR (total fertility rate)- average number of
births a woman will have over her lifetime - 2.1 is replacement rate (a woman in a country
must have this many children for pop to grow) - Doubling Time- time it takes for a population to
double (p. 48) - Invest 100 at 10 interest, it will take 7
years to double over and over again - Today our pop is doubling every 51 years (it
recently slowed was much faster) - The worlds growth rate is 1.4, 80 mil people
added each year
20Total Fertility Rates
Fig. 2-9 The Total fertility rate (TFR) is the
number of children an average woman in a society
will have through her childbearing years. The
lowest rates are in Europe, and the highest are
in Africa and parts of the Middle East.
21World Population Growth19502000
Fig. 2-6 Total world population increased from
2.5 to 6 billion in this half century. The
natural increase rate peaked in the early 1960s
and has declined since, but the number of people
added each year did not peak until 1990.
22Growth at the Regional Scale
- High growth rates are associated with low
standing of women (no education, male dominated) - China is worlds largest, but soon to take over
is India - Japans pop is shrinking, along with other
wealthy countries - Russia is shrinking- horrible conditions (drug
use, alcoholism, economics) lower births raise
deaths
23- South America is experiencing significant
reduction in natural population growth rates,
whose rates were high a generation ago. Brazil is
down from 2.9 in the mid 1960s to 1.3 today. - Economically wealthier countries have a declining
growth rates. Economically prosperous countries
have high levels of education, later marriage,
family planning which lower the population
growth. Russias declining population growth
rates are due to social dislocation that has come
in the wake of the collapse of the Soviet Union. - Cultural traditions also influence rates, like
religion has an impact on family planning.
24Pop growth at the Local Scale
- Most countries have variations within their
borders - Population trends show that Sub-Saharan Africas
growth rate is higher than India in spite of the
AIDS epidemic. - Muslim countries of North Africa have high growth
rates. - Saudi Arabia has one of the highest growth rates
in the world. - India- pop explosion in the 50s
- Encouraged family planning (birth control, forced
sterilization after 3 children for men) - Led to riots 22.5 million sterilizations
- TODAY guns for sterilization program- 2
sterilizations for shotgun, 5 for revolver - Landowners abusing laborers and sterilizing them
for guns
25Maharashtra, India. A sign reads free family
planning sterlization operation closed in 1996.
26The Demographic Transition of Great Britain
- In Great Britain, demographers used church data
such as baptisms and funerals to study changes in
the population. - The expected rate of natural increase may vary
over different periods of time. To study the
natural increase, demographers calculate the
crude birth rate (CBR) and the crude death rate
(CDR). - Before the Industrial Revolution, Great Britain
experienced high birth rates and death rates with
little difference between the two. The result, a
low population growth. - After industrialization, the death rate started
to fall due to better medicines and standards of
living, the population began to explode.
27HIV/AIDS Prevalence Rates, 2002
Fig. 2-26 The highest HIV infection rates are in
sub-Saharan Africa. India and China have large
numbers of cases, but lower infection rates at
present.
28- From the 1800s through 1950 population continued
to growth at a low, but stable rate because the
birth rates were still higher than the death
rate. - Today both birth and death rates are low,
resulting in slow, stabilizing population growth. - Britain provides a model for the four stages in a
demographic cycle. Demographers call the sequence
of stages in population growth the demographic
transition model.
29Demographic Transition in England
Fig. 2-14 England was one of the first countries
to experience rapid population growth in the
mid-eighteenth century, when it entered stage 2
of the demographic transition.
30The Demographic Transition (p. 54)
- Low growth stage (also called low stationary)-
high birth rate and high death rate, little long
term growth - High- growth stage (also called early expanding)-
high birth rate, declining death rate- large
growth of population - Moderate-growth stage (also called late
expanding)- declining birth rate, low death rate-
slow continued pop. Growth - Low-growth stage (high stationary)- low birth
rate, low death rate- very low rate of growth
31- Stage 1 epidemics, plagues, famines keep death
rates high, lots of births required to survive - Stage 2 usually corresponds with technological
development- medicines and farming improve - Stage 3 associated with urbanization and the
economic cost of having more children (no longer
needed for farming) - Stage 4 associated with highly educated and
working women
32Population Composition
- Shows the number of men, women, and their ages in
a population - Population composition is easily displayed in a
population pyramid - Pyramids allow geographers to take a quick look
and tell the following - Ages, growth rates, males vs. females, wealth,
cdr, cbr, and many other things
33Percent of Population under 15
Fig. 2-15 About one-third of world population is
under 15, but the percentage by country varies
from over 40 in most of Africa and some Asian
countries, to under 20 in much of Europe.
34Population Pyramids in U.S. Cities
Fig. 2-16 Population pyramids can vary greatly,
with different fertility rates (Laredo vs.
Honolulu), or among military bases (Unalaska),
college towns (Lawrence), and retirement
communities (Naples).
35Rapid Growth in Cape Verde
Fig. 2-17 Cape Verde, which entered stage 2 of
the demographic transition in about 1950, is
experiencing rapid population growth. Its
population history reflects the impacts of
famines and out-migration.
36Moderate Growth in Chile
Fig. 2-18 Chile entered stage 2 of the
demographic transition in the 1930s, and it
entered stage 3 in the 1960s.
37Low Growth in Denmark
Fig. 2-19 Denmark has been in stage 4 of the
demographic transition since the 1970s, with
little population growth since then. Its
population pyramid shows increasing numbers of
elderly and few children.
38Important Population Terms that Show the
Condition of a Country
- Infant Mortality Rate (IMR)- the number of deaths
during a babys first year of life per 1000 - Child Mortality Rate (CMR)- the number of deaths
during ages 1-5 per 1000 children - Life Expectancy- average age that someone will
remain alive in a country - These reflect overall health of a society
- AIDS has lowered life expectancy for Sub-Saharan
Africa - Women live longer than men (why?)
- World average was 68 for women and 64 for men
recently - How do these statistics show the condition of a
countrys development???
39Aging Populations
- To replace the population, TFR must be 2.1.
- - TFR in Bologna, Italy is 0.8
- - Why are women having fewer children?
- What are the impacts of an aging population on a
country? - What are the solutions to an aging population?
40Dependency Ratio
- 0-14 Dependents
- 15-64 Workers
- 64 Dependents
- DR Number of Dependents (0-15 and 65)
- Number of Working-age (16-64)
X 100
41Population policies
- -set up by governments with the purpose of
influencing the overall growth rate or ethnic
ratios within the population - 3 types
- Expansive Population Policy-
- Encourage large families and raise the rate of
natural increase - May be done because populations are aging and
declining - Ex Sweden suggested showing racier programming
at night to raise birth rates - -Tax breaks, job flexibility, cash payments by
government
42- Eugenic Population Policy-
- Done in the past and are designed to favor one
racial or cultural sector of the population over
others - Nazi Germany is an example
- Done covertly through unfair taxation, biased
allocation of resources, etc.
43- Restrictive Population Policy-
- Seek to reduce the rate of natural increase
- Most popular in todays societies
- Chinas one child policy is an example
44Sex Ratio
- Sex Ratio number of males per hundred females
- In general more males are born than females
- Males have higher death rates
- Examples
- Europe and North America 95100
- Rest of World 102100
- Major issue for China with 1 child policy!
45Use of Family Planning
Fig. 2-22 Both the extent of family planning use
and the methods used vary widely by country and
culture.
46Crude Birth Rate Decline, 19812001
Fig. 2-21 Crude birth rates declined in most
countries between 1981 and 2001 (though the
absolute number of births per year increased from
123 to 133 million).