Please enable JavaScript.
Coggle requires JavaScript to display documents.
Population structure. Population pyramids to programm the future - Coggle…
Population structure. Population pyramids to programm the future
The natuarl sex ratio at birth is estimated to be close to 1.06 males/females
However males tend to have higher death rates (lower life expectancy)
As a consequence, the sex ratio tends to reduce as age increases
In the 20th century life expectancy rose by 30% and in MEDCs 75% of people is expected to live over the age of 75.
Issues of an ageing population
labour shortages
increased spending on medical services for the elderly
fall of the total population
under-use of some services (schools)
more people need pensions for a longer time
Changes in MICs [India]
Wide base (quite high birth rate)
The fall of this rate started with the population policies against large families
sides above the age of 30 (relative lack of healthcare)
Death rate at a low level
Many people are under 20 yo, so the population will continue to grow
However in 2070, will start to fall as a consequence of the impact of a falling bith rate
Changes in HICs (Gulf State- Qatar)
Massive bulge on the male side 20-50 --->foreign forkers
Implication of this fast-growing population
Lack of work, food supply, housing (developing of squatter settlements)
Increased traffic congestions and atmospheric pollution
Not enough resources and services
Overuse of agricoltural land and increased overgrazing
deforestation and loss of natural vegetation and habitat
LEDCs
Narrow shape at the top = low life expectancy
Higher death (and immigration) rate in the gap between young dependance and adults
Wide base = high birth rate
Women live longer than men
MEDCs
Gap in 30-34 due to higher death rate, emigration or lower birth rate
Women live longer than men
Broad shape at the top (high life expectancy)
narrow base