Urbanization and Settlement Patterns
Site and Situation
- Site: A city's physical location with favorable features (topography, resources, climate).
- Examples: Mesopotamia, Egypt, and the Indus River Valley.
- Situation: How a site connects to other sites; its relative location.
- Example: Hangzhou, China, thrived due to its location on the Grand Canal.
Urbanization
- Definition: The development of densely populated settlements (cities).
- Influenced by: Transportation, communication, population growth/migration, economic development, and government policies.
Impact of Technology and Migration on Urbanization
- Telegraph, telephone, and internet: Increased business efficiency and global communication.
- Migration: Rural-to-urban migration driven by lack of opportunities in rural areas.
Cities: Types and Growth
- Megacity: Regional population over 10 million, typically in peripheral/semi-peripheral countries.
- Metacity: Regional population over 20 million, mostly in peripheral/semi-peripheral countries e.g. Tokyo and Delhi.
- Early 20th-century growth: Fueled by affordable cars (Model T, assembly line).
Urban Expansion
- Urban Sprawl: Unplanned expansion leading to decentralization.
- Suburbanization: Movement to suburbs enabled by cars.
- Edge Cities: Semi-independent communities on urban edges with downtown areas and transportation access.
- Exurbs: Low-density areas beyond suburbs, inhabited by wealthier citizens.
- White Flight: Urban sprawl led to racial segregation as white populations moved to suburbs.
- Boomburb: Rapidly growing suburb with over 100,000 residents.
- World City: Urban area influencing global economy and finance (e.g., New York City).
Urban Models
- Rank-Size Rule: City size distribution where the second largest city is half the size of the largest, etc.
- Primate City Rule: One city is disproportionately larger than others in a country (e.g., Mexico City).
- Christaller’s Central Place Theory: Explains settlement sizes based on their relationship to a central place.
- Central Place: Top of the hierarchy.
- Threshold: Number of people needed to support a service.
- Range: Distance people travel for goods/services.
- Gravity Model: Interaction between two places is based on size and proximity.
- Interaction \propto \frac{Population1 \cdot Population2}{Distance^2}
CBD and Land Use
- CBD Housing Costs: Expensive, low density; commercial land use predominates.
- Zoning Regulations: Laws dictating land use (residential, commercial) affecting population density and location.
- Infilling: Developing underused land within urban areas for housing/commercial sites.
- Infrastructure: Systems supporting populations (roads, hospitals).
Sustainability in Cities
- Importance: Using resources for future generations.
- Types: Smart growth policies, New Urbanism, greenbelts, slow-growth cities.
- Smart Growth: Combats sprawl with environmental protection and walkable areas.
- New Urbanism: Focuses on walkable neighborhoods and mixed land use.
- Smart Transportation: Public transportation over cars.
- Greenbelts: Natural barriers preventing urban sprawl.
- Slow-Growth Cities: Use zoning to slow urban sprawl.
- Census Data: Quantitative data used for understanding population composition and size.
- Qualitative Data: Interview-based data to gauge feelings on urban issues.
Urban Challenges and Solutions
- Social/Economic Challenges: Redlining, blockbusting, housing affordability, rising crime, environmental injustice.
- Disamenity Zones: Areas lacking basic amenities.
- Squatter Settlements: Structures built from discarded materials (disamenity zones).
- Inclusionary Zoning: Requires affordable housing in new developments.
- Local Food Movements: Urban gardens for nutritional food access.
- Urban Renewal Initiatives: Targeted run-down areas for demolition and rebuilding leading to displacement.
- Gentrification: Rebuilding deteriorating areas, displacing lower-income residents.
Urban Sustainability Issues
- Sanitation: Waste disposal problems in peripheral/semi-peripheral countries.
- Climate Change: Cities radiate heat due to hard surfaces (urban heat islands).
- Air and Water Quality: Pollution and lack of clean water, especially in rapidly growing areas.
Solutions to Urban Problems
- Regional Planning Efforts: Coordination across local governments.
- Brownfield Remediation: Cleaning up polluted industrial sites.
- Urban Growth Boundaries: Limits to contain city growth.
- Farmland Protection Policies: Prevent conversion of agricultural land.
Urban Models
- Burgess Concentric Zone Model: City grows in circles from CBD.
- CBD, Zone of Transition, Working Class, Middle Class, Upper Class.
- Hoyt Sector Model: City develops in wedge-shaped sectors along transit routes.
- Harris and Ullman Multiple Nuclei Model: City develops around multiple nodes, not just the CBD.
- Galactic City Model: Decentralized CBD influence with suburban edge cities connected by highways.
- Latin American Model: CBD and market established by colonial law, spine with upper-class housing, zones for different income levels.
- Southeast Asian Model: Trading ports replace CBD; high-class residential near port; market gardening zone; squatter areas.
- African Model: Multiple CBDs (colonial, traditional, modernizing); ethnic neighborhoods; squatter settlements.