IB Geography 1.1.3 Population Distribution and Development at the National Scale Notes

Development Concentrates in a Core, and People Follow It

1. Inside a single country, economic development is almost never spread evenly.
2. A core region concentrates investment, industry, services and well-paid work.
3. A periphery supplies labour and raw materials, and lags behind in income and infrastructure.
4. Once the gap opens it tends to widen on its own.
   1. Investment creates jobs, and jobs attract migrants.
   2. The larger local market that results then attracts further investment.
   3. The periphery loses working-age people at the same time, which shrinks its market and its tax base.

1. Three processes connect distribution to development at this scale: voluntary internal migration, core-periphery patterns and megacity growth.

Voluntary Internal Migration Is the Mechanism That Moves People

1. Voluntary internal migration is movement within a person's own country, undertaken by choice.
2. The dominant flow is rural to urban, driven by wages, formal employment, education and services.
   1. Movement that people are compelled into is forced migration, so it should not be labelled voluntary.
3. Migration is selective by age, because it is mostly young adults who move.
   1. Cores therefore gain workers of childbearing age.
   2. Peripheries are left with older populations and fewer births.
4. Money flows back along the same route, because migrants send earnings home to households that stayed.
5. Not all movement is permanent, since circular and seasonal migrants return home between periods of work.

Megacity Growth Is Where the Core-Periphery Pattern Becomes Visible

1. The UN counted 8 megacities in 1975 and 33 in 2025.
2. Most of that growth is in middle-income countries, where in-migration and natural increase add population at the same time.
3. Neighbouring cities can merge into a continuous mega-region.
   1. The Pearl River Delta links Guangzhou, Shenzhen, Foshan, Dongguan and Hong Kong into one near-continuous built-up belt.
   2. The Yangtze River Delta does the same around Shanghai.
4. A megacity is usually the visible centre of the national core, so the two patterns are the same process seen at different scales.

China: One Country with Two Population Geographies

1. The physical baseline
   1. Eastern China has fertile plains such as the North China Plain, plus the Yangtze and Yellow rivers for water and transport.
   2. Western regions including Tibet and Xinjiang are arid or mountainous, with little arable land.
2. What economic policy added
   1. Special economic zones from 1980 concentrated export manufacturing on the southern and eastern coasts.
   2. Most movement was from inland provinces towards coastal employment centres such as Shenzhen, Guangzhou and Shanghai.
3. The scale of the movement
   1. China's urban population share rose from 19.4% in 1980 to 65.9% in 2024, while Australia's changed only from 85.8% to 87.6%. National definitions of urban differ, so these figures are best used to compare long-term trajectories rather than as perfectly identical measures.
   2. The 2020 census counted a migrant workforce of 285.6 million.
   3. Of those, about 170 million were working outside their home area, and the rest worked locally.
4. The brake on it
   1. The hukou household registration system ties access to schooling and healthcare to a person's registered home area.
   2. Migrants can take city jobs while remaining outside that city's welfare system, which produces a large population living where it is not registered.

Australia: Coastal Cities Surround a Sparsely Settled Interior

1. The national pattern
   1. Australia is highly urbanized, with its urban population concentrated near the coast rather than spread across the continent.
   2. Australia's 2021 State of the Environment report estimated that 87 percent of the population lived within 50 kilometres of the coast in 2019.
   3. The 2021 Census recorded 66.9 percent of Australians in Greater Capital Cities, most of which sit on the coast.

1. What the physical geography limits
   1. Much of the interior is desert, where low and highly variable rainfall restricts farming and permanent settlement.
   2. Rainfall generally increases toward the coast because proximity to moisture sources and rain-producing weather systems improves.
   3. Mining and extensive grazing operate across the interior without producing a continuous urban belt because both use large areas and relatively few workers.

Economic Opportunity Reinforces the Coastal Pattern

1. Why the coastal cities stay dominant
   1. Large European colonial settlements developed around coastal ports, which fixed early government and transport networks near the sea.
   2. Sydney, Melbourne, Brisbane, Perth and Adelaide concentrate jobs, universities, services and transport links that attract further population.
   3. Internal migration changes which coastal and regional centres grow fastest without removing the broad coast-interior contrast.
2. Why resource wealth does not fill the interior
   1. Interior mining towns and pastoral stations are separated by vast distances, so resource extraction creates isolated nodes rather than a densely settled core.
   2. Many mining operations use fly-in fly-out workforces, so the place of production differs from the workers' permanent homes.
   3. Australia therefore has a resource-rich periphery with low population density, while its coastal cities remain the main population and service core.

China and Australia: Concentrated Populations with Different Spatial Logics

1. The shared pattern
   1. China's National Information Center reports that about 94 percent of the population lives east of the Hu Line on 43 percent of the national territory.
   2. Australia's coastal belt held 87 percent of the population in 2019, leaving the continental interior sparsely settled.
2. The physical contrast
   1. Eastern China's river basins, plains and monsoon rainfall support dense farming and urban settlement.
   2. Australia's dry interior lacks the reliable rainfall and connected water systems needed for a comparable settlement belt.

Economic Development Magnifies the Populated Regions

1. The human reinforcement
   1. China's coastal core expanded through export manufacturing, infrastructure investment, state policy and voluntary internal migration.
   2. Australia's coastal pattern grew from port-based colonial settlement and is reinforced by jobs, services and transport in the major capitals.
2. The urban scale
   1. China's eastern core contains megacities and near-continuous mega-regions, whereas Australia remains highly urbanized without a city above the 10 million megacity threshold.
3. The judgement
   1. Physical geography set strong starting constraints in both countries, while development and migration intensified the advantages of their populated regions.