Population Growth
Population Growth
Questions to consider:
What is overpopulation?
What is carrying capacity?
Is overpopulation a world problem?
What are the limiting factors for
population growth?
Carrying Capacity
Carrying capacity is the number of
individuals an environment can support
without significant negative impacts to
the given organism and its environment.
Below carrying capacity, populations
typically increase, while above, they
typically decrease.
What is overpopulation?
Overpopulation is a condition where an
organism's numbers exceed the carrying
capacity of its habitat.
The supportable population of an organism,
given the food, habitat, water and other
necessities available within an environment
is known as the environment's carrying
capacity for that organism.
Resources Needed to Sustain Life.
The resources to be considered when
evaluating whether an ecological niche is
overpopulated include clean water, clean
air, food, shelter, warmth, and other
resources necessary to sustain life.
In the case of humans additional resources
are considered, such as medical care,
education, proper sewage treatment and
waste disposal.
World Population from 10,000 BC
to Today.
World Population From 1000 AD to
Today
Countries by Population Density
Map of countries by population density
Population Density in 1994
Areas of high population densities, calculated in 1994.
Fertility Rates By Countries
Map of countries and territories by fertility rate
United Nation's population
projections by location.
Factors Effecting Population Growth
Fresh water.
Food
Land
Energy
Wealth and poverty
Water
Food Production
Usable Land
Usable land may become less useful
through desalination, deforestation,
desertification, erosion, and urban sprawl.
The space taken by a human being itself is
not a problem. Land to support his/her
needs is a problem.
Energy
This is a topic that we will deal with in the
future.
Wealth and Poverty
Economic Freedom: A Comparison of Two Nations
“North Korea and South Korea have similar population
densities, natural resources, and even parallel cultures
(ethnically based in Korean) sharing the same peninsular
homeland; but, whereas North Korea is a poverty-stricken,
totalitarian dictatorship [120][121] where its people are
suffering from widespread famine and are destitute,
[citation needed] South Korea is a prosperous, capitalist
country where the people are well nourished and
materially/economically secure, despite the fact that South
Korea's population is double that of North Korea. This
suggests that it is bad economic polices, not
"overpopulation," that causes famine. Various Indices of
Economic Freedom suggest that countries with a strong
level of economic freedom avoid famines, regardless of
how high their population densities.[122] “
Taken from Wikipedia at http://www.wikipedia.org/Overpopulation.
Wealth vs. Family Size
The theory of demographic transition, while
unproven to apply to all world regions, holds that,
after the standard of living and life expectancy
increases, family sizes decline. Factors cited in the
decline of birth rates include such social factors as
later ages of marriage, the growing desire of many
women in such settings to seek careers outside of
child rearing and domestic work, and the
decreased need of children in industrialized
settings
Mitigation Measures
While the current world trends are not
indicative of any realistic solution to human
overpopulation during the 21st century,
there are several mitigation measures that
have or can be applied to reduce the
adverse impacts of overpopulation.
Growth Predictions
1900
– Africa - 133 million
– Asia - 946 million
– Europe - 408 million
– Latin America & Caribbean - 74 million
– Northern America - 82 million
2050
– Africa - 1.9 billion
– Asia - 5.2 billion
– Europe - 664 million
– Latin America & Caribbean - 769 million
– Northern America - 445 million[15]
Will We Have to Leave the Earth?