Population distribution and density Human elective.

Population distribution and density

Human elective

Population distribution

People spread across the world

Distribution is very uneven

Places difficult to live include mountains and deserts, places attractive to live places with resources

Population density Average number of people living per sq km Related to population and the land

available Calculated by dividing the population by

the land area High population density: Java has a

population den. Of 5000 per sq km Low population density: Amazon rainforest

has a pop. den. of 3 per sq km

Factors affecting population distribution and

density

Physical factors:1) Climate: where people live comfortably, crops can grow

successfully 90% of the world pop live in the northern

hemisphere temperate zone Pop den. Highest in the region= long growing

seasons ie. Europe and North East USA

Factors affecting population distribution and

density

Physical factors:2) Relief: Flat low-lying areas = high densisties 80% of pop live in altitudes below 500m Mountainous regions have low pop den Building infrastructure easier in flat

lands, better communication networks

Factors affecting population distribution and

density

Physical factors:3) Soils: Fertile soils attractive for crops

(brown earth soil) Mountains tend to have poor soils,

thin or infertile, discourages living conditions

Factors affecting population distribution and

density

Physical factors:

4) Drainage: Areas with rivers more densely

populated Water for farming, industry, to live Provide fertile soils (alluvial soils) Transport (River Rhine) Egypt: 90% of people live within 6km of

the Nile

Factors affecting population distribution and

density

Physical factors:5) Resources: Regions with mineral deposits

attract industries Leads to major settlements such

as coal mining in the Same Bemuse region

Factors affecting population distribution and

densityHuman factors:

1) Government: Regions with stable political systems have

higher pop den. ie. Europe since the 2nd world war

Offer peace and justice as well as services Political conflict zones lead to refugees

fleeing lower the population Government schemes ie. Sponsored

resettlement brings people to more sparely populated areas

Factors affecting population distribution and

density

Human factors:2) socio-economic: Economic growth offers job

opportunities Change can be seen in growth ie.

Ireland where people move from west-east

Religion: Utah high pop den of Mormons

Factors affecting population distribution and

density

Human factors:3) Historic: Conquest and colonisation ie.

Plantations Events such as the Famine (low

pop den)

Population growth Influenced by birth and death rates, migration Birth rates: number of live births per thousand

of a population Death rates: number of deaths per thousand of

a population Natural increase: difference between birth and

death rates, when birth rates are higher than the death rates

Natural decrease: when death rates are higher than the birth rates

Factors influencing birth and death rates

1. Education and status of women (social)

2. Standard of living (economic)3. Government policy (social)4. Religion, society and customs

(cultural)

1. Education & status of women (social factor)

Education allows women to make personal decisions about family size.

More knowledge of health care-healthier children-lower child mortality-no need for more children to support elderly-low birth rate

Better job opportunities-less desire for big family-low birth rate

Older when leave education-fewer fertile years available-fewer children born

2) Standard of living(economic factor)

High standard of living=low birth rates and death rates

Cost of raising a child in Ireland over 8000 per year for the 1st 8 years

Access to clean water and better healthcare

Less developed countries no government support

Large families=economic advantage High birth rates and death rates due to

poor health care and services

3) Government policy(social factor)

China one child policy (1974), importance of boys in society

Romania (1960’s) abortion outlawed, childless people over 25 had to pay extra tax (10-20% of income), allowances for children increased

Russia birth rates low leading the governement to pay families for children (almost 7,000 for 2nd and 3rd child)

Paris Region – extra money for a third child, long maternity leave etc.

4) Religion, society and customs

Catholic influences strong=birth rates higher (South America) due to opposition to contraception and termination

Society place demands: India having sons economic advantage (dowry)

Women encouraged to have more sons to increase family wealth

5) Fertility rates Total fertility rate: average number of

babies born to women during their reproductive years

Influenced by the previous four factors To replace its population country

needs a TFR of 2.1 children per women

Several European countries below this, Ireland currently at this

AIDS

One of biggest threats to life expectancy

In 2007 39,000,000 suffers worldwide

Anti-retroviral drugs prolong life Drugs too expensive for many 3rd

world countries

World Population

History

Patterns in Population Growth

Initial pop low so growth was low Agriculture started 12,000ya in middle east,

asia and europe Malthus believed natural disaster necessary to

keep pop down - Famines, diseases and war kept pop low

Prior to good transport accessibility to food was limited which affect pop growth also

Persecution by local laws contirbuted to deaths of high numbers

1750 world pop began to grow rapidly:

•Agricultural Revolution - New farming methods & improved technology… crop rotation, better farm machinery, use of seed

drill, better animal breeds, all of these increased food production

•Industrial Revolution - Invention of steam engine….factories & coalfields developed -- employment, improved income, new

housing and dev. of towns, absorbed the increasing working population

•Medical Revolution - Improved hygiene & medicine, eliminated diseases, longer & healthier life

These aided the pop explosion over past 60 yrs

Life expectancy from 40 in 1950 to 75 in 2010 and expected to be 82 in 2050

Stable pop worldwide means 2.1 children per family…. Europe as low as 1.56 but Latin America = 4; Africa = 6

Industrialisation, increased income, medical & education dev. led to lower death rate and higher pop.

Regional Growth patterns over time & space

1990… 1.2 billion in developed world & 4.1 billion in less dev.

Half worlds pop was in east & south Asia… China 1.2 billion & India 960 million. Europe 15% America (N&S) 14% Africa

12%

By 2025 Africa's share of world pop will double, south Asia & Latin America will remain constant & east Asia into relative

decline.

Developed world drop form 23% to 17% in terms of world pop.

Falling Pop numbers:

Western Europe…. EG Switzerland & Sweden will have zero growth rates by 2010, North Am. By 2030 & China by 2070.

Problem: Shortage of skilled labour, science & technology graduates & shortage of taxes to sustain pensions & services.

Demographic Transition Model

Countries go through predictable changes as the country develops economically 5 stages to pass through

The Population Cycle – Stages 1-5

Stage 1: High birth rate, high death rate. Low population growth due to famine, disease, and natural disasters. Underdeveloped region – dependent on agriculture. E.g. Somalia (Europe 1700)

Stage 2: The economy improves. Money is spent on healthcare and clean water. Birth rate stays high, death rate drops a dramtically. Population increases. E.g Nigeria and Bangladesh (Europe 1800’s)

Stage 3: Social and economic development continues. People start having less children as most children survive to adulthood, lower infant mortality. Population increase slows but continuous increasing e.g. China, Mexico (Europe early 20thC)

Stage 4: Low birth rate and death rate. Small population growth.The country is now wealthy. Women have an improved standing in society. Family planning is widespread. E.g. Ireland, Thailand

Stage 5: The death rate is higher than the birth rate. People have very few children. The population starts to decline. Population in decline Germany and Italy

Ireland expected to reach this stage in 20yrs

Factors Affecting Population Change

The Status of Women

When women are educated and involved in careers outside the home they have less children.

This greatly reduces the population growth of a country.

3 Children FamiliesAfter 3 generations

there are 27 children being born.

2 Children FamiliesAfter 3 generations

there are only 8 children being born.

Dependency ratio This is the ratio between the non-working

population ( children under 15 and elderly dependents over 65) and the workers ( the economically active adults 15 and 65).

To get the dependency ratio for a country we add the number under 15 and the number over 65, divide this into the 15 to 65 age and multiply by 100.

Ireland 2002.Under 15 = 827,428Over 65 = 436,001

Between 15 and 65 = 2,653,774DR for Ireland 2002 = 0.48 ie 48 dependents per 100 workers or 1

per 2.1 workers.

Population pyramid

Three types progressive, stationary, regressive

Population pyramid

Progressive: wide base narrow top (stage 1-3)

Stationary: square shape (stage 4)

Regressive: wide top narrow base (stage 5)

Population pyramid Carefully study the population pyramids of Kenya and

India. For both countries 1. Calculate the total percentage (male & female) aged between

0 and 14 years2. Calculate the total percentage ( m & f) aged 65+.3. From your calculations state which country has (a) the highest

percentage of children; (b) the highest percentage of old people.

4. From your study of the population cycle, explain the reasons for the %s in 3a and 3b.

5. Which of these countries could best afford free (a) primary education; (b) secondary education and (c) third level. Explain each of your answers.

6. Which pyramid shape indicates (a) an industrially emergent country; (b) a newly industrialized country? Explain.

Population pyramid

Case study: China

The one child policy 1949-1976: population grew by several

hundred million Average fertility: 6 children per mother Pursued vigorously in urban areas: one

child allowed Rural areas second allowed if first is a girl Fines and penalties apply to those who

don’t comply

China problems associated to the one child policy

Gender bias Resulted in imbalance in the sexes of

babies Ratio of 106.7boys: 100 girls cenus fig.

believed to be as high as 117:100 Need for agricultural labour Pride in sons (tradition) some families

consider it a dishonour not to have a male heir

China problems associated to the one child policy

Female abortion Some couples have ultrasounds to

identify the sex of the baby (rural areas in the 2nd child)

Led to widespread abortion of female foetus

1995 law passed banning abortion based on gender, reported that despite this female abortion and infanticide continue

95.7% of foetus aborted are female

China problems associated to the one child policy

Non registered births Birth of females are sometimes not

registered leading to females living in illegal limbo

90% children in orphanages are abandoned girls

Results of one child policy

Transition from high birth rate to low birth rate

Moved from stage 2 to stage 4 Population still growing due to vast

amount of young married couples (9million + annually)

Case study: Ireland

Changes in density and distribution Pre famine(1845-1848)agricultural

rural economy(pop. 8million +)(113km sq)

Post famine: emigration and death reduced pop.

Early 20th century move of people eastwards urban areas (GDR)

Today 66% of Irish live in urban areas

Case study: Ireland

Population density and distribution Lowest in west, midlands & Islands

Some fertile lands have low density also as settlement retricted

Highest density in coastal lowlands and river valleys e.g Blackwater Well drained, fertile land and sea

ports at river mouths

Change over time: Post famine emigration continued, Reached there lowest levels in 1960

(2.6 million) (39km sq) Economic growth and in migration in

1960’s Lemass Era (economic policies), MNC,

jobs, inwards migration, EEC 1973

First pop growth in 120 yrs between 1971 and 1981

1980’s Recession & Emigration, 200,000 people emigrated during 80’s

1990’s Celtic Tiger, inward migration, urbanisation due to concentration of jobs in these areas

66% of population today urbanised Largest increase in East Dublin, Louth Kildare, Wicklow up by

40% Recession again in recent times so

emigration returned Despite this pop expected to reach

5m by 2015

Case study: Ireland

Changes in population structure Population aging (greying)rapidly Present: over 65s =11% of population Under 15’s down 10% since 70’s 2020= 14% of population over 65 2050= 29% of population over 65 Birth rate halved since 1980’s at 4 Economically active group (15-64yrs) up

from 58% to 68% in 45yrs

Dependency Ratio highest in 1966 at 74% is now at 46%

Predicted to rise again as pop ages Consequences:

Pensions, Nursing Homes, greater tax burden

TFR is 1.98 - maintenance is 2.1 Life expectancy since 1926

Men – 57.4 – 76.8 Women 57.9 – 81.6

Advances in Health Care, Dr Noel Browne eradicated TB

Sean Lemass Taosieach 1959-1966 “A rising tide lifts all boats” 1st programme for economic expansion T.K Whitaker Moved away from protectionist policies £220m Free Trade – 1961 failed attempt to join

EEC Free education 1969

Case study: France

Distribution France population of 62.1million 50% population occupy over 10%

of the population 1930’s: urbanisation increased 2007: 77% of population living in

urban areas

Case study: France

Areas of densest population1. Paris area & lower part of the Seine

river(11m, 20% of pop)2. The Lyon area3. The Rhone valley4. The Mediterranean coast5. The Loire, Garronne and Rhine valleys6. Brittany coast7. Industrial area in Lorraine

Case study: France

Places less densely populated1. Great forests2. Eastern part of the Paris basin3. The Ardennes4. Mountainous zones, the alps5. Massif central 6. The Pyrenees7. Corsica

Case study: FrancePopulation growth in France

18th century France saw a fall in death rate Rapid population growth in 2nd half of 19th &

20th C World War population growth moderate Post war population growth: rose by 23million

to 62.1million Death rate: stable at less than 10 per

thousand Birth rate: Highest TFR in Europe at 8.65 per

thousand in 2011