How Population Changes Shape Urban Growth
Urbanization
Urbanization is the increase in the proportion of people living in urban areas compared to rural areas.
Urbanization: The Growth of Cities
Urbanization is driven by two primary forces:
- Natural Increase: When the birth rate exceeds the death rate, leading to population growth.
- Migration: The movement of people from rural to urban areas in search of better opportunities.
Natural Increase
Cities often have relatively high birth rates due to:
- Younger Populations: Urban areas attract young adults who are more likely to start families.
- Improved Healthcare: Access to better medical facilities reduces infant mortality and increases life expectancy.
While urban areas initially attract young people, leading to increased birth rates, over the longer term, urban populations tend to have fewer children per household (lower fertility rates) compared to rural areas.
ExampleIn Shanghai, the population grew from 11 million in 1978 to over 24 million in 2015, partly due to natural increase.

Migration
- Migration is a key driver of urban growth, especially in developing countries.
People move to cities for:
- Economic Opportunities: Jobs in industries, services, and technology.
- Access to Services: Better education, healthcare, and infrastructure.
- Improved Quality of Life: Modern amenities and social opportunities.
- Mumbai, India, has experienced rapid urbanization due to rural-urban migration.
- Migrants are drawn to the city’s booming economy, despite challenges like overcrowding and inadequate housing.
Centripetal Movements: Pulling People into Cities
- Centripetal movements are forces that draw people toward urban areas.
- Two major types are rural-urban migration and re-urbanization leading to inner-city gentrification.
Rural-Urban Migration
Rural-Urban Migration
This is the movement of people from rural areas to cities.
- It is driven by push and pull factors:
Push Factors Making People Leave Rural Areas
- Lack of Opportunities: Limited jobs and low wages in rural areas.
- Poor Infrastructure: Inadequate healthcare, education, and transportation.
- Environmental Challenges: Droughts, floods, or land degradation.
Pull Factors Attracting People to Urban Areas
- Economic Growth: Higher wages and diverse job opportunities in urban areas.
- Better Services: Access to quality education, healthcare, and social amenities.
- Modern Lifestyle: Urban areas offer entertainment, cultural activities, and connectivity.
In Nigeria, cities like Lagos have grown rapidly as rural residents seek jobs in manufacturing and services.

When studying rural-urban migration, always consider both push and pull factors. This helps explain why people leave rural areas and why they choose specific cities.
Re-urbanization and Inner-City Gentrification
Re-urbanization
Re-urbanization is the process in which people move back to urban areas that have previously experienced decline or depopulation, often leading to revitalization through demographic shifts, infrastructure improvements, and increased economic activity.
This process is often associated with gentrification, where an influx of wealthier residents leads to the renovation and upgrading of neighborhoods.
- Gentrification occurs when wealthier individuals move into older, often neglected urban neighbourhoods, renovating properties and attracting new businesses.
This process has both positive and negative effects:
Positive Effects
- Revitalization: Improved infrastructure, housing, and public spaces.