Population, migration and settlement

Population geography studies the distribution, composition and movement of people. Population size is the number of people in an area at a given time. Population density relates that number to area, commonly as people per square kilometre. A large population does not necessarily imply high density: a very large country may contain many people but still have a low average density because its land area is extensive.

Calculate arithmetic density by dividing population by land area. If a district contains 120,000 people in 300 square kilometres, its density is 400 people per square kilometre. This average can hide considerable local variation. Most residents may occupy a few towns while other parts have few inhabitants. A map of distribution therefore gives information that a single density figure cannot provide.

Population changes through births, deaths and migration. Natural increase is births minus deaths; net migration is immigration minus emigration. Total population change combines the two. Rates express these events relative to a population over a stated period and are different from raw numbers. If a question provides rates per thousand, convert them carefully instead of treating them as percentages.

Migration is a change of usual residence. Push factors encourage people to leave an origin, while pull factors attract them to a destination. Limited employment, insecurity or environmental stress may push; jobs, education or family links may pull. These influences can operate together. A journey to work each morning is commuting, not necessarily migration, because the person's usual residence may stay unchanged.

A settlement's site is the actual land on which it stands, including local conditions such as slope and drainage. Situation describes its position relative to other places, transport routes and resources. Rural and urban settlements may perform several functions, including farming, trade, administration or industry. Urbanisation is an increase in the proportion of a population living in urban places, not simply any growth in one town's population. In explanations, connect a population trend to both opportunities and demands for services. Avoid assuming that migration is always harmful or always beneficial; its effects depend on the scale, timing and capacity of the receiving and sending communities.

Population change has several components

Population increases through births and immigration and decreases through deaths and emigration. Natural increase concerns births minus deaths, while net migration concerns arrivals minus departures. When crude birth and death rates are expressed per thousand people per year, their difference is also per thousand and must be divided by ten to express a percentage. A birth rate of 32 per thousand and death rate of 12 per thousand gives natural increase of 20 per thousand, or 2% annually before migration. State the period and do not treat the rate as an exact forecast for every later year.

A population pyramid displays age and sex composition using a stated classification. A broad base can indicate many young people relative to older groups, while a narrower base can reflect lower recent births, migration patterns or other history. A pyramid is not an automatic diagnosis of a country's economy. Cohort sizes reflect past events as well as current conditions. When discussing dependency, distinguish a demographic age-based ratio from actual employment: some people of working age are not employed, and some outside the conventional age range work.

Distribution and density need scale

People are unevenly distributed because of interacting physical and human factors. Water supply, climate, relief and soils can influence settlement, while jobs, transport, security, historical decisions and services shape where people can live and work. A dense settlement in a challenging environment may depend on technology and trade. A fertile area may remain sparsely populated for historical or institutional reasons. Avoid explaining every distribution with one physical factor or assuming that population density directly measures quality of life.

National average density can hide concentrated urban corridors and sparsely occupied areas. Arithmetic density divides total population by total land area, while other density measures use different denominators, such as agricultural land. Always identify the measure. Comparisons also require compatible dates and boundaries. A city that annexes nearby settlements may show an apparent population jump partly because its administrative area changed. A responsible explanation checks whether growth reflects real demographic change, migration, reclassification or a mixture.

Migration involves origin and destination

Push factors encourage departure, while pull factors attract movement towards a destination. Examples include employment opportunities, education, environmental stress and family connections. A single move can involve several motives, and people may face barriers such as cost, documentation, discrimination or limited information. Distinguish internal migration from international migration and temporary movement from a lasting change in usual residence. Daily commuting is not automatically counted as migration under a definition requiring a change of residence.

Migration can bring workers, skills, remittances and cultural connections, while also creating challenges such as pressure on housing or loss of particular workers from an origin area. Effects differ among groups and over time. Remittances may support households but do not guarantee development of every locality. Avoid describing migrants only as a burden or assuming that all leave for the same reason. A geographical answer should identify the scale and the affected groups, then explain the mechanism behind the proposed effect.

Settlement patterns and functions

A settlement may be dispersed, nucleated or linear according to the arrangement of buildings. Its site refers to the local physical setting, while situation concerns its relationship with other places and routes. A river crossing, port or road junction can influence situation, and a defensible hill or water source can influence site. These factors interact with history and planning. Settlement function describes roles such as administration, commerce, industry, transport or education. Many settlements have several functions that change over time.

An urban hierarchy groups settlements by size, services and influence, but administrative labels vary between countries. Higher-order services often draw people from a wider area, while common low-order goods may be supplied in many small centres. A sphere of influence is the area from which a place draws users or over which its functions have effects. It is not necessarily a neat circle. Transport links, competition, cost and specialised services can make influence uneven. Use supplied evidence rather than assuming that the largest city supplies every service everywhere.

Urbanisation and planning

Urbanisation is an increase in the proportion of people living in urban areas, not simply an increase in the number of buildings. Urban population can grow while the urban share remains unchanged if rural population grows at a similar rate. Rapid expansion can put pressure on water, sanitation, transport and housing, especially when investment and governance lag behind demand. It can also support economies of scale, innovation and access to services. Planning choices influence which benefits and costs occur and who experiences them.

Sustainable settlement planning connects land use, transport, flood risk, livelihoods and accessible services. Improving one road without considering drainage may shift a problem rather than solve it. Upgrading services in an existing neighbourhood can have different effects from relocating residents far from work. There is rarely one universal solution for every city. In an exam answer, choose a specific problem, explain its cause, propose a relevant measure and consider a practical limitation. This is stronger than a list of unrelated projects.

Self-check

A hypothetical district with 240,000 people over 800 km² has an arithmetic density of 300 people km⁻². If its annual births are 6,000, deaths 2,000, arrivals 1,500 and departures 500, total change is +5,000 for that period. These are illustrative figures, not measurements of an actual Nigerian district. Identify the boundary and date whenever real statistics are used. Finally, distinguish population growth, urban growth and urbanisation, since each asks a different question about demographic change.

Comparing the syllabus's world examples

The Amazon Basin illustrates how dense forest, transport access, environmental conditions and settlement history can coincide with relatively sparse occupation over large areas. North-eastern United States illustrates historical industrial and urban networks, while India and Japan show that dense populations must be explained through varied agricultural, historical, economic and urban conditions rather than one climate. Along parts of the west coast of southern Africa, aridity limits settlement in some areas, but ports, mining and other activities create local concentrations. These are broad comparative patterns, not current population statistics or claims that every part of a named region is uniform.

Settlement comparisons among Western Europe, the United States, the Middle East and West Africa should consider water, transport, history, land systems and economic functions. An oasis settlement, a suburban metropolitan corridor and a West African market town may have different site and situation relationships. Rural and urban places exchange food, labour, services, capital and information, so they are not separate economies. Use a current atlas and dated local case study for specific place detail. A general comparison prepares the reasoning but does not replace evidence from the map or case supplied in an examination.