Chapter 8POPULATION STUDIES

POPULATION DISTRIBUTION, Diversity and Change

Learning outcomesin this chapter you will learn that:

• The population cycle explains how birth and death rates change over time

• Population density varies from place to place

• A country’s population structure is shown on a “Population Pyramid”

• High densities and low densities have social and economic effects

• Poor countries have higher death rates than rich countries

POPULATION DENSITYTHE WORLDS POPULATION IS 6BILLION

SOME AREA ARE:VERY DENSELY POPULATED……A LOT OF PEOPLE

LIVE IN CERTAIN PLACES

VERY SPARSLY POPULATED…..NOT MANY PEOPLE LIVE THERE.

TERMS

• POPULATION DENSITY: THE AVERAGE NUMBER OF PEOPLE PER SQUARE KILOMETRE

• POPULATION DISTRIBUTION: WHERE ALL THE PEOPLE LIVE IN AN AREA

• FOUR AREAS OF HIGH POPULATION DENSITY ARE:

• NOTRH-EAST AMERICA• WESTERN EUROPE• INDIA, PAKISTAN, BANGLADESH• CHINA, JAPAN, INDONESIA

Population distribution around the world

Where do all the people in the world live?

What is the population of Ireland in 2005?

Ireland’s population 4.1 million

What is the population of the world in 2005?

World population 6,477 millionOver six billion people living in the world

How big is this figure?

• One billion = One thousand million• One billion= 1,000,000,000• It would take you eleven days to count to one

million if you allowed one second for every number you counted

Population growth

• In the past, population growth was slow and uneven.

• Populations fluctuated because of wars, famine, disease.

• People were dying because of a lack of medicine

Today’s population growth• The population of the world is growing: by over 200,000 people every day

This means that the birth rates are greater than the death rates = the population grows

The birth rate is the number of babies born per year for every 1,000 people in the total populationThe death rate is the numbers of people dying per year for every 1,000 people in the total population

What happens to the population if the death rates are higher than the birth rates??

How do you calculate the population growth?

• 40 people are born• 15 people die• 40 – 15 = 25 per 1,000

25/1000 x100% = 2.5 % per year

Where is the population growth happening in the world?

• Today most of the population growth is in developing countries: Asia and Africa

• This is because people in poorer countries regard children as a source of income. When they retire, their children can provide a wage to help support their family

POPULATION GROWTH

• IN RICH COUNTRIES TODAY THE POPULATIONS ARE GROWING SLOWLY

• IN POOR COUNTRIES TODAY THE POPULATIONS ARE GETTING BIGGER VERY QUICKLY

• SO……...WE CAN USE HOW RICH OR POOR A COUNTRY IS

• ……..TO TELL WHAT IS HAPPENING TO ITS POPULATION

• LETS LOOK AT EUROPE OVER THE PAST 200 YEARS

The population cycle

STAGE ONE

• 200 YEARS AGO THE INDUSTRIAL REVOLUTION HAD NOT STARTED IN EUROPE

• MOST PEOPLE LIVED IN THE COUNTRYSIDE AND WERE FARMERS

• BIRTH RATES AND DEATH RATES WERE VERY HIGH. Famine, disease and natural disasters caused high death rates

STAGE TWO

• As the economy of a country improves, the government spend money on health services and clean water is available

• Birth rates remain high• Death rates begin to fall• The population begins to grow

STAGE THREE

• Economic growth continues; People are more educated and they begin to plan family sizes.

• Families have fewer children so the birth rates begins to fall

• Death rates are still low

STAGE FOUR

• Countries are wealthy in this stage.• Parents continue to plan their family size• Birth rates are low• Death rates are low as most people survive to

old age• Ireland is considered to be at this stage now

Stage 5

• The death rate is higher than the birth rate because the population is now elderly

• Women are having fewer children• Germany is at this stage now

Factors that affect population change

1. Food Supply2. Improved Technology3. Health4. War5. Status of Women6. Education

Food supply affects population growth

Food supply

Examples of food supply affecting populations in Ireland and Brazil

• 1800 Ireland had population of 4.5 million• Potato was main food.• By 1845 population grew to 8 million• 1845-1848 famine. 1 million died

• 1900 Brazil: population was 17 million• 2007 population was 192 million. Why?• Immigration and high birth rates• Farmers cleared land for agriculture-rice, maize, vegetables and fruit

2. Improved Technology helps with population growth

Improvedtechnology

3. Health affects changes in population

Health

Examples of how health is different in rich and poor countries

• Rich country: water supply available: Safe drinking water and sanitation

• Disease such as Tuberculosis has been wiped out due to availability of medication

• Poor countries: Water not available in rural areas. They have a well which is unsafe-contaminated by animals….cholera

Population Pyramids

• Population pyramids show the structure of the population

• Age structure of the population. This is the proportion of people in different age groups.

• Sex structure of the population. This is the proportion of males to females.

POPULATION STRUCTUREThe population pyramid displays the age

and sex structure of a country or given area

Population inFive Year

Age bands

Usually, but not always,In % to make for easier

comparisonsbetween countries

OLD DEPENDANTS

ECONOMICALLYACTIVE

YOUNG DEPENDANTS

FEMALESTo the rightMALES

To the left

Population Pyramid

Population structures of Brazil and Germany

Population pyramid Ireland

Ireland 2025

IRELAND 2050

Population pyramid for Brazil

Brazil is a country with a rapidly expanding poulation.

• A wide base tells us that birth rates are high:• Lack of family planning, high rate of infant

mortality, traditional role of women in society• A narrow peak tells us that death rates are

high: this is because of• poor living standards, lack of good food, poor

medical services, lack of clean water

Germany population pyramid

Germany is a developed country

• A narrow base indicates low birth rates.• This is because of high rates of education = family

planning, low infant mortality rates, women work outside the home, good access to medical services, Germany is industrialised so children are not needed to work in the primary sector (digging fields, mines)

• A wide peak indicates low death rates: this is due to high living standards, good medical services and a developed economy

Irelands Population Pyramid

Ireland is a developed economy

• A narrow base indicates low birth rates but there is an increase in the 0-4 age category in ireland

• The reasons are the same as Germany..education/family planning…

• The wide peak indicates low death rates as older people live longer. Life expectancy is high. Women live on average to 80 yrs and 75 for men in Ireland

• Why?

Life Expectancy

Life expectancy is the average number of years which new born children can be expected to live.

Life Expectancy

Let’s look at page 215 of our book: Question 2which pyramid represents a developing country and why?

Calculate the percentage of the population that is 4 years and under.

Question 1 on page 215: look at the information on the table and answer the following questions

(B) IN WHICH TABLE ARE THE 2 DEVELOPED COUNTRIES?(B) WHICH IS THE LEAST DEVELOPED COUNTRY?

country Birth rates per 1000 Death rates per 1000

% population under 15 years

A 13 12 19

B 42 16 39

C 32 8 41

D 16 9 22

E 44 19 42

2012 junior cert geography paperName 1 country similar to Aname one country similar to Bexplain why B has wider base than Aname 2 uses of population pyramids

Population density and population distribution

• Population density = average number of people living in a square kilometre. Areas with high population densities can have problems such as overcrowding, lack of clean water, pollution and lack of open spaces

• Population distribution = the dispersion of people around the world: where people live. It is very uneven. People avoid very hot, dry, humid or cold areas. Example-Sahara desert, Greenland

World population densities

Percentage share of worlds population by continent

Lets recap what we did the last day

• What information do population pyramids give us?

• Describe what a pyramid for a developing country would look like

• Describe what a pyramid for a less developed country would look like

• Why do these countries have high birth rates?

Here is an interesting article from Saturday’s Irish Times

• Listen to this article and make notes about anything that strikes you

• This article is about one of the most dangerous places in the world to have a baby

• Sierra Leone• High rates of maternal and infant mortality

At the end of todays class you will be able to:

• Explain what a high population density means• list the problems that are caused by high

density• Describe life in Kolkata• Examine and discuss the problems caused by

overcrowding in Kolkata

High population densities

• Overpopulation means that there are too many people living in an area relative to resources and technology to provide an adequate standard of living

• An adequate standard of living means having access to clean water, shelter, food and clothing

• Areas with high population densities include Kolkata (Calcutta) India and Hong Kong (China)

High population density has an effect on the social and economic geography of an area.

Kolkata was the new name given to Calcutta in 2001

• Kolkata is in India and has one of the world’s largest populations

• It has over 10 million people and is called a MEGA CITY

• many areas have 32,000 people per square kilometre

• 500,000 people are pavement dwellers• It is a manufacturing city with a large port

A day in the life of the real slumdog millionaires India

Programmes to help street children in Kolkata

Taj Mahal New Delhi

Homework for today

• Monday 1st October• Write an essay on a typical day in the life of a

person living in Calcutta• Points to include: overcrowding, shortage of

clean water and lack of open space