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Chapter 22: Urbanization and Sustainable Cities

Overview of Urbanization

• Historically, most of humanity lived in rural areas, relying on natural resources.

• The Industrial Revolution marked a significant shift towards urbanization.

• Prediction: Over the next 30 years, 3 billion people will move to cities.

• Emergence of vast urban agglomerations (mergers of municipalities) worldwide.

Urban Population Statistics

• Table 22.1: Urban Share of Total Population (%)

  • 1950: World: 29.4%, North America: 63.9%, Latin America: 41.4%, Africa: 14.4%, Asia: 17.5%, Europe: 51.3%, Oceania: 62.4%

  • 2000: World: 46.7%, North America: 79.1%, Latin America: 75.5%, Africa: 35.6%, Asia: 37.4%, Europe: 70.8%, Oceania: 70.4%

  • Projected 2050: World: 67.2%, North America: 88.6%, Latin America: 86.6%, Africa: 57.7%, Asia: 64.4%, Europe: 82.2%, Oceania: 73.0%

Urbanization Trends

• Graph illustrates urban and rural population changes from 1950 to 2030 across development levels:

  • Urban growth in more developed areas versus less developed.

Definition of a City

• City Definition by U.S. Census Bureau:

  • Any incorporated community, urban if >2,500 residents.

• Rural areas: residents depend on natural resources.

• Urban areas: residents typically work in non-resource-based occupations.

• Difference in settlements:

  • Village: Linked by culture, customs, family, land.

  • City: Supports specialization in various fields (arts, services).

World's Largest Cities

• List of major cities with over 10 million population, e.g., Beijing, Tokyo, Delhi, and more.

• Notable population statistics from 1984 to projected 2025.

Urbanization Statistics

• In 1900, only 13 cities had populations exceeding 1 million; by 2016, there were 500.

• Demographic shift: China leads with substantial urbanization impact.

Causes of Urban Growth

• Two primary factors:

  • Natural Increase: Improved food supplies and sanitation.

  • Immigration: Influenced by push and pull factors.

Immigration Factors

• Push Factors:

  • Overpopulation, economic issues, racial/religious conflict, land ownership issues, changes in agriculture (e.g., monoculture farms).

• Pull Factors:

  • City vibrancy, job opportunities, housing, entertainment, social mobility, professional specialization.

Urban Challenges in Developing World

• Uncontrollable Growth Issues:

  • Traffic congestion from rapid vehicle growth exceeding road construction.

  • Air pollution from poorly maintained vehicles and other sources.

  • Inadequate sanitation and water supply: only 35% have satisfactory sanitation, with one-third lacking safe drinking water.

Current World Housing Problems

• Slum Population: Minimum of 1 billion live in inadequate tenements or shantytowns.

• Squatter Towns: Informal settlements where people occupy land without ownership.

• Homelessness: Around 100 million lack any form of housing.

Developed World Urban Issues

• Industrialization-related urban growth has stabilized or reversed in many areas, with numerous environmental problems addressed.

• Movement of major polluters and businesses to developing countries.

Urban Sprawl in Developed Areas

• New housing developments often occur beyond city borders, impacting agricultural land and leading to longer commutes and reduced urban tax bases.

Improving Urban Liveability: Mass Transit

• Case example: Curitiba, Brazil - a high-speed bus system designed for efficiency and accessibility.

Smart Growth Principles

• Encourage efficient land resources and infrastructure use.

• Focus on reducing wasted space, democratic planning, mixed land uses, and preserving natural spaces.

New Urbanism Concept

• Aim to restore small-town qualities in larger cities through modular planning.

• Focused accessibility to services and promoting diverse housing options.

Green Urbanism Initiatives

• Transition from greenfield development to redeveloping existing cities with a focus on ecological sustainability.

• Encourages infill, high density, and mixed-income housing, along with alternative transportation solutions.

Open Space Design Principles

• Contrast traditional suburban layouts with conservation development promoting open spaces.

• Importance of views of landscapes, wildlife, and community pathways.