Population dynamics. IGCSE Geography, IB Geography

1. POPULATION DYNAMICS
WHY POPULATION SIZE CHANGES

2. THE SIZE OF A POPULATION DEPENDS ON A BALANCE BETWEEN
SEVERAL THINGS
Birth rates Death rates
Immigration
Emigration
Population change, is the difference in the size of a population between the end
and the beginning of a given time period (usually one year).

3. CRUDE BIRTH RATES: The number of
live births per 1000 people in a
population. Expressed /1000 or as a
percentage. 21/1000 or 2.1%
CRUDE DEATH
RATES:The number
of deaths per 1000
people in a
population.
Expressed /1000 or
as a percentage.
natural population change
(sometimes “natural increase”) is the
number of live births minus the
number of deaths.
http://epp.eurostat.ec.europa.eu/statistics_explained/index.php/Glossary:Population_change

4. ACTUAL INCREASE (or “actual population
change”) takes NET MIGRATION into account
when calculating the changes in the population
size of an area.
Migration refers to the number of migrants,
people changing their residence to or from a
given area (usually a country) during a given
time period (usually one year).
http://www.movingpeoplechangingplaces.org/uploads/images/migration_peoplemap_smaller.jpg

5. Immigrants are people arriving or
returning from abroad to take up
residence in a country for a certain
period, having previously been resident
elsewhere Immigration
net migration ;the number of immigrants
minus the number of emigrants
Emigrants are people leaving the country where
they usually reside and effectively taking up
residence in another country Emigration
http://www.jaha.org/edu/discovery_center/push-pull/img/Ellis01.jpg
http://www.irishtimes.com/blogs/generationemigration/files/2013/02/departuregates.jp
g
http://epp.eurostat.ec.europa.eu/statistics_explained/index.php/Glossary:Population_change

6. Birth Rates Immigration
Birth rate and immigration
increase the size of the
population
NATURAL CHANGE MIGRATION
POPULATION
Death rate and emigration
decrease the size of the
population
Death Rates Emigration

7. Both the CBR and CDR can be examined more
closely by looking at other indicators such as:
General Fertility Rate: (GFR) the number of
births per 1000 women aged 15-49 years.
Total Fertility Rate: (TFR) - the total
number of children a woman would bear
during her lifetime.
Child
Mortality
Rate: the
number of
deaths in
children under
the age of 5
per 1000
children.
Infant Mortality Rate: The number of
deaths of children less that 1 year old per
1000 live births.
Life
Expectancy:
The average
number of
years a
person can be
expected to
live.
http://dontgiveupworld.com/wp-content/uploads/2013/05/Quote-on-life-and-death.jpg

8. http://bashapedia.pbworks.com/f/birth_rate.gif
http://upload.wikimedia.org/wikipedia/commons/d/d7/Death_rate_world_map.PNG
Death rate
Compare and contrast*
these two maps. Write
your observations in
your notebook.
* What is the same, what is
different?

9. The demographic transition model attempts to explain
the change in countries from having high birth and death
rates to low birth and death rates.
In developed countries this transition began in the eighteenth
century and continues today. Less developed countries began the
transition later and are still in the earlier stages of the model.
The model is based on the change in crude
birth rate (CBR) and crude death rate
(CDR) over time.
http://geography.about.com/od/culturalgeography/a/demotransition.htm

10. DEMOGRAPHIC TRANSITION MODEL