Natural Change
The difference between the number of births and deaths in a country or region.
This can be natural increase or natural decrease
Natural Increase
birth rate - death rate
Natural Decrease
death rate - birth rate
Birth rate
The number of live births per 1000 of the population
Death rate
the number of deaths per 1000 of the population
Fertility rate
the average number of children a woman had during her lifetime.
if the fertility rate is >2.1, there will be population growth.
- in 2010, 87 countries were either at or below this level, showing fundamental and dramatic social change which allowed more children to be educated and more women to work
Infant mortality rate
the number of children under the age of 1 who die, per 1000 live births, per year
Life Expectancy
the average number of years from birth that a person is expected to live
Factors affecting fertility - demographic , social ,ecomomics, poltical
Factors affecting fertility can be grouped into 4 main categories:
- demographic - this includes population factors such as mortality rates. In societies where infant mortality is high, parents tend to have more children to compensate for unexpected deaths.
Example: in Somalia, infant mortality is high at 65 deaths/1000 live births so fertility rates are also high at 5.98 births per woman. however in Japan, infant mortality is low at 1.8 deaths/1000 live births so fertility rates are also low at 1.36 births per woman. - social/cultural - in some societies, tradition demands higher rates of reproduction. women’s opinion here matter little compared to intense cultural expectation.
Female literacy reduces fertility rates. education on birth control/ greater social awareness provides a wider choice of action. Formal education gives greater opportunity for employment usually leaving little/no interest/time for babies
Example: literacy rates in Somalia is 38%, fertility rate is 5.98 births per woman. Literacy rates in Japan is 99% , fertility rate is 1.36 births per woman.
Religion is also an important factor
Example: Islamic and Roman Catholic religions oppose artificial birth control - Economic - in LICs, children are seen as an economic asset due to labor they provide as well as the expectation for them to support their parents in their old age. In HICs, cost of child-dependency years is a major factor in the decision to extend the family. HICs provide workplace childcare and flexible working time to avoid loosing valuable female workers
- Political - in the last century, many governments have attempted to change the rate of population growth for economic and strategic reasons.
Example: during the late 1930’s, Germany, Italy and Japan all offered inducements and concessions to those with large families.
Factors affecting mortality
- injury related death - murder, road-traffic accidents, war industrial injury
- medical infrastructure - areas with a shortage of medical facilities/trained medical staff
- disease (communicable/non-communicable) - lifestyle illness, cancer, alcoholism, pandemics, epidemics
- famine and drought
- population structure - more old people -> more deaths
- poverty - no facilities, no proper food/nutrition, poor healthcare
- infant mortality
- economic development - mortality decreases as country gets richer
- HIV/AIDS
Example: sub-Saharan Africa (Botswana)
Categories of age groups on the age/sex diagram
young(0-14)
active(15-64)
old(65-85+)
population structure
refers to the number of males and females within different age groups in the population
dependency
reliance for survival on the support provided by another/ others
dependency ratio
the relationship between the economically active and non-economically active population, where the economically active population is usually taken as being between ages 15-65, regardless of employment status or not.
dependency ratio
the relationship between the economically active and non-economically active population, where the economically active population is usually taken as being between ages 15-65, regardless of employment status or not.
dependency ratio formula
(non-economically active population/economically active population)*100
DTM
the DTM is a theoretical model showing possible changes in birth and death rates that may take place in a country over time
what happens in stage one of the DTM
stage one of the DTM the birth rate is high but the death rate is also high so there is no natural increase as there healthcare is low and sanitation is low while there is no use of contraception.
stage 2 of the DTM
at stage 2 the birth rate remains high but the death rate decreases due to better healthcare and access to that health care. so there is high natural increase
stage 3 of the DTM
the birth rate fall rapidly as there is better education and access to contraception and better wages so people do not need extra children for work while the death rate also remains low so the rate of natural increase decreases.
stage 4 of the DTM
the birth rate is low while the death rate is also low so there is no natural increase
stage 5 of the DTM
death rate starts to rise above the birth rate as the baby boom of before starts to die off so now there is a natural decrease
Advantages of the DTM (4)
Easy to understand.
Universal concept cam be applied to all countries.
Flexible timescales.
Allows comparisons to be made.
criticisms of the DTM
Original model did not contain a 5th stage, and can’t predict when changes will occur for a country.
Eurocentric, so assumes all countries will follow the way that Europe developed.
Ignores regional differences within a country.
Does not consider migration, government policies or war/disaster events impacting a population.
Diseases such as HIV/AIDS can put the model in reverse.
