Effects of high and low
population densities
Areas with high population densities can
be seriously polluted with lack of water,
services and open spaces.
 Areas with low population densities can
have land abandoned, high immigration
rates and low marriage rates.


India has close to one billion people living
in its country. Calcutta is one of India’s
most densily populated cities with over 15
million people living in the city.

Poor migrants that come from other parts
of Inida live in slums around the edge of
the city called shanty towns or bustees.

Problems that people in Calcutta face are
overcrowding, lack of open space, lack of
clean water and pollution
Overcrowding

The population density
in Calcutta is 35000 per
square km, this make
calcutta one of the most
densily popullated cities
in the world.

This overcrowding
results in overcrowded
homes been made of
loose material and more
than half a million
people having no
homes at all.
Lack of open
space
This overcrowding
also results means
there is very little
open space in the
city, unlike modern
cities like Dublin and
London.
All space in the city
is taken up by
houses or bustees.
Clean water
With the city
expanding up along
the Hooghly river for
50 km the river gets
easily polluted. Only
rich people can
afford the technology
for filtering water.
The rest of the
popullation use dirty
river water which
results in diseases.
Pollution
The bustees and
slums of calcutta
have many types of
pollution with sewage
and other waste in
open drains which
floods during the
monsoon season.
There is also a large
amount of garbage
the litter that pile up
with nobody
employed to move it.

Hong kong located in the south of china is
another city affected by overcrowding. It
is rich compared to Calcutta but some of
its inhabitants are still poor. It is one
hundred times more densely populated
than Ireland.

Kong kong suffers the same problems as
Calcutta such as overcrowding, lack of
open space, lack of clean water and
pollution.
Hong kong
Overcrowding
Becasue of the severe
population density
many peopl live in
shanty towns or poor
apartments. The city
has expanded upwards
as well as outwards to
meet the rising
population.
The city is so
overcrowded that
schools run a 16 hours
system with students
having a choice of
coming in the morings
or the evenings.
Lack of open
space
In mainland Hong Kong space
is at a premium. On the
fringes on the city there is
more space with new housing
estates being developed.
Space is so scarce in the city
itself that industries are
building on polders which is
land that is reclaimed from the
sea.
Clean water
Becasue Hong Kong is a
modern city there is a clean
supply of water, but the
beaches and sea are full of
industrial waste and sewage
making it impossible to go
swimming.
This problems was highlighted
in the olympics where any
sailors who fell into the sea
quickly fell sick
Pollution
Air pollution in Hong
Kong is immediately
evident from the
constant fog that
hangs over the city.
This smog is a result
of traffic pollution.
There is also a high
level of noise and
visual pollution with
ugly high rise
buildings.

With low population densities, where
areas are under populated there is often a
very low marriage rate, political and
economic isolation and abandoment of
agricultural land.

Examples of areas with low population
densities are the West of Ireland, and Mali
in Africa.
Low population density
Low marriage
rates in the
west of Ireland
Which
means a fall
in the
population
This results
in a falling
birth rate
Isolates ares
have few
jobs, third
level college
or leisure
facilities
This results
in many
people
migrating to
cities
With these
young
people gone
there are
fewer
marriages

With this decline in population and the
migration of young people, there are less
and less people to farm the land which
becomes abandonded.

With the older generation left to farm the
land by themselves the EU give grants
and pensions to Elderly farmers who turn
their land into forestry.
Abondement of Land
Becasue of the lack of population there is a
lack of representation, with the west of
Ireland having fewer TD’s than the east of
Ireland.
 Economically the west suffers also with a
lack of infrastructure such as roads and
services.
 Because of its location on the west coast of
Ireland it is in fact isolated from Irelands
political and economic hub which is Dublin,
its surrounding counties and other main
cities.

Political and Economic Isolation

Mali is a landlocked country in West Africa
with a populaiton density of 10 people per
square km.

The reasons for this are to do with the
lack of precipitation, the Sahara Desert
and desertification which leads to drought
and famine, making it one of the worlds
poorest countries.
Mali

As in Ireland many young people migrate
to the country’s main cities for jobs. Due
to Mali’s traditions it is mostly young
males who migrate which leaves a surplus
of females in the countryside, this reduces
marriage rates and reduces the population
Marriage Rates

Due to severs drought and desertification
most of the rural population has been
forced to abondon its land with thousands
of acers been destroyed by the desert and
entire animal herds being wiped out.

These people flee to the main cities of
Mali in searh of employment, health care
and better educational services.
Abondonment of Agricultural land
Population migration

Mali was once a colony of France, becasue
of the lack of population and the fact that
the population is scattered mean the road
and communication networks is poorly
developed, making it hard to sustain a
vibrant economy.

Also becasue the country is landlocked
this makes it very hard to attract a
foreign market
Political and economic isolation