Population: notes

Measuring Population

• Density: people per square kilometre. Distribution is where people live.
• Birth rate and death rate: births and deaths per 1000 people per year.
• Natural increase: birth rate minus death rate.
• Dependency ratio: the young and old (dependants) compared to the working age group.

Distribution

• Dense: fertile land, good rain, jobs, water, mining areas and cities.
• Sparse: deserts, steep mountains, tsetse fly areas, thick forest.

Migration

• Rural to urban: push factors (poor land, no jobs) and pull factors (jobs, schools, clinics).
• Effects: crowded towns and empty villages with old people and children.
• Population pyramid: wide base means high birth rate; narrow top means few old people.
• HIV and AIDS: raised death rates and lowered life expectancy in Zimbabwe.