Changing populations and places

A country's **age and sex structure** — males left, females right, youngest at the bottom.

How a population is divided between **young, working-age and old** people.

**Under-15s and over-65s**, who rely on the working-age (15–64) population.

The **balance of males to females** in a population (often per 100 females).

**Birth rate − death rate** (per 1000 per year); it **excludes** migration.

A **youthful** population — high birth rate, fast growth.

An **ageing** population — low birth rate, more elderly.

Women tend to **live longer**, so they dominate the oldest age groups.

It is often young **men** moving for work, leaving more females at the source.

**Identify** = read a value off; **Describe** = report the pattern (shape + figures), no reasons.

An urban area with a population of **10 million or more**.

In **lower- and middle-income** countries, mostly in **Asia and Africa**.

**China and India** — both have huge, fast-growing urban populations.

Housing shortages / **slums** and **traffic congestion** with air pollution (also pressure on water, sanitation and jobs).

More, **better-paid jobs** and **economic growth** (megacities drive national GDP); also better access to services.

Unplanned, often self-built housing (a **slum**) that grows when a city expands faster than it can house people.

A **better-paid job** (economic) or access to schools and hospitals nearby (social).

Megacities create wealth, drive **national GDP**, and make services cheaper to provide to people living close together.

**Highest value minus the lowest** value.

**Identify** = read it off; **Estimate** = a sensible figure from the axis; **Determine** = work out a value (e.g. a range).

Alongside slums and pollution there are real **benefits** — jobs, services and economic growth — so a balanced answer is needed.

With an explicit, **justified judgement** supported by named megacities and data.

Movement that people are **compelled** to make by a serious threat to life or livelihood -- they have no real choice.

Forced migrants are **pushed out** by danger; voluntary migrants move by **choice** (e.g. for work).

A forced migrant who has **crossed an international border** to seek safety.

Someone forced to flee who **remains inside their own country**.

**Political** (conflict, persecution), **environmental** (drought, flooding), **social** (persecution of a group) and **developmental** (dams, mines).

Violence destroys homes and threatens lives, so people flee for **safety**.

Crops fail and water runs out, so people leave to **survive**.

They strip nearby land for fuelwood and **pollute or overuse water**, degrading the local environment.

A sudden influx can **strain a host country** and raise tensions or instability.

**Syria** -- civil war from 2011 forced over 6 million people abroad as refugees.

**Three Gorges Dam, China** -- reservoir flooding relocated over 1 million residents.

**Subtract** the earlier year's value from the later year's value, and quote the units.

Choosing to move home **within your own country** (no border crossed and not forced).

**Source** = the place migrants leave; **destination** = the place they move to.

Arrivals minus departures - **positive** means a place gains people, **negative** means it loses them.

**Push:** few jobs / poor services in the source. **Pull:** more jobs / better services in the destination.

An **ageing**, shrinking community as young adults move away.

A younger, growing population but **pressure** on housing, schools and hospitals.

Source regions **lose their workforce** and stall while cities are **overwhelmed**.

Mostly **young, working-age adults** - the group the economy relies on.

**Highest value minus the lowest value** (e.g. +97,000 to -107,000 = a range of 204,000).

People may **misremember**, give vague answers or not be honest, and surveys only **sample**.

A few places gain heavily and a few lose heavily, so change is **uneven**, not uniform.