UNIT 1 CHANGING POPULATION
◼ How does population
◼ What factors affect
structure affect
birth and death?
◼ Why do people choose
to move?
◼ What are the impacts of
migration?
economy?
Number
Structure
Movement
Distributio
n
◼ What factors affect
distribution?
1.1 Population and economic development patterns
Physical and human factors affecting population distribution at the global scale
Global patterns and classification of economic development:
◼ low-income countries
How population varies between places ◼ middle-income countries and emerging economies
◼ high-income countries
Population distribution and economic development at the national scale, including voluntary internal
migration, core-periphery patterns and megacity growth
◼ Two detailed and contrasting examples of uneven population distribution
How can we graphically demonstrate
distribution?
Population distribution at the
global scale
What factors affect population distribution?
Population density 人口密度
◼Arithmetic population density describes the number of
people living in a given area, usually a square kilometer.
◼Physiologic population density, the number of people per
unit area of agriculturally productive land.
Egypt, 84 people per square kilometer (2017)
Egypt, 2620 people per square kilometer (2017)
Sparsely populated
or
Densely populated?
Factors affecting population density
Physical factors:
Human factors:
◼Relief 地形起伏
◼Transportation
◼Climate
◼Economic development
◼Vegetation
◼Political stability
◼Soils
◼Historical reasons
◼Water supplies
◼Mineral resources
The Lorenz curve show the distribution of wealth in a South American city.
(i) Describe what line A represents. [1]
It shows equality in the distribution of wealth by households/a line of perfect equality [1].
(ii) Estimate what percentage of the city’s total wealth belongs to the wealthiest 10 % of
households. [1]
32 % (Allow 30–33 %) [1]
(iii) Referring to the graph, outline the evidence that many households in this city suffer from
poverty. [2]
Award [1] for valid evidence, and [1] for further development, including development of
numerical evidence. For example: The 25 % of households that are least wealthy share less
than 1% of the wealth [1]. This means that many households will be living on very few dollars a
day equivalent and struggling to survive [1].
World Bank’s economic development
division
High-income countries
(HICs)
More than $13205
Upper middle-income $4256–$13205
Middle-income countries
(MICs)
Lower middle-income $1086–$4255
Low-income countries
(LICs)
less than $1085
◼ An emerging economy 新兴经济体 is a country that has some characteristics of a developed market, but does not satisfy
standards to be termed a developed market. This includes countries that may become developed markets in the future.
Population distribution at the
national scale
- Internal migration, core-periphery
and megacities
Key Terms
◼Voluntary internal migration
The movement of population away from their home, from one part of a country to another. It occurs
when people are free to move where they choose.
◼Core-periphery
A more-developed part(core) of a country, and a less-developed part(periphery) of a country, a
region or the world.
◼Megacity 超大城市
A city with more than 10 million inhabitants.
超大城市
1000 万以上
特大城市
500-1000万
大城市
100-500万
中等城市
50-100万
Area
36%
64%
Population
Southeast
Northwest
6%
94%
Southeast
Northwest
The Core-periphery model
• most prosperous
• Capital city or the chief port
Core
• Major urbanized and industrial areas
• High level of wealth and economic
activities
• Under-developed
Periphery
• Usually rural areas
• Relatively low level of wealth and
economic activities
Megacity
Global
pattern
◼ How do megacities distribute globally?
Causes
◼ What factors affect the growth of megacities?
Consequ
ences
◼ What are the impacts of rapid growth of megacities?
Megacity
• Asia:
Tokyo, Shanghai, Beijing, Guangzhou, Chongqing, Manila 马尼拉 菲律宾, Dhaka 达卡 孟加拉, New Delhi 新德里 印度,
Mumbai 孟买 印度, Karachi卡拉奇 巴基斯坦, Jakarta 雅加达 印尼
• Europe and North America:
London, Paris, New York, Los Angeles, Moscow, Mexico city
• South America:
Sau Paulo 巴西 圣保罗, Rio de Janeiro 里约 巴西, Buenos Aires 布宜诺斯艾利斯 阿根廷
• Africa:
Cairo 开罗 埃及, Lagos 拉各斯 尼日利亚
Push – pull
factors
Rural-urban
Natural
migration
increase
Megacity
Assignment 2
Using examples, explain the pull factors and
obstacles.
Pull factors
Obstacles
More and better jobs
…
Lower levels of crime
…
…
…
Push and pull factors
Push factors
Pull factors
The mechanization of farming activities and a shortage of alternative jobs
More schools, doctors and healthcare services are available in the urban
resulting in a lack of employment opportunities in rural areas and high
areas.
levels of rural unemployment
Some large landowners take back land from their tenant farmers to grow Successful migrants encourage their extended families and other
cash crops for export.
members of their rural communities to join them in th large urban areas.
High infant mortality in many rural areas due to a lack of clean water,
electricity, sanitation and healthcare.
Natural disasters, for example droughts.
Lack of infrastructure, such as good roads, education facilities, shops
In Brazil, a series of advertising campaigns were carried out in rural
areas in the 1950s and 1960s to attract workers from rural areas to
move to the city.
• The age-selective (and often gender-selective) nature of
migration can have a very significant impact on both areas of
origin and destination.
• Age/sex structure diagrams for rural areas in LICs and MICs
frequently show the loss of young adults (and their children) and
may also show a distinct difference between the number of males
and females in the young-adult age group, due to a higher number
of males than females leaving rural areas for urban destinations.