Summary
Highlights
The session kicks off with a welcome to the Unit 6 live review, emphasizing the importance of the Course Exam Description (CED) as the guide for testable content. The presenter highlights key topics like site and situation, and the influence of transportation on urbanization, encouraging viewers to review any unfamiliar terms.
The discussion begins with distinguishing between site factors (specific characteristics of a location like arable land or flat terrain) and situation factors (relative location, trade routes, or protection from mountains). These factors explain why cities were built in particular areas and how they connect to other places.
The presenter explains how advancements in transportation, communication, population growth, and migration patterns have significantly influenced urban areas. For example, the development of the interstate system allowed people to live farther from the Central Business District (CBD), changing the spatial layout of cities.
A clarification on mega cities (over 10 million residents) and meta cities (over 20 million residents) is provided, noting a historical error in the slides. The trend of these large cities increasingly appearing in periphery and semi-periphery countries due to rapid population growth is highlighted.
Urban decentralization is defined as the movement of people and resources away from urban centers, often into suburbs and rural areas. This shift impacts economic and political power. Urban sprawl, an unchecked outward expansion of cities with low-density development, leads to increased car dependency, traffic, pollution, and infrastructure costs.
Boombs are rapidly growing suburban areas with their own identities. Exurbs are even farther out, characterized by low population density and fewer services, often relying on larger cities. Edge cities are areas with high concentrations of businesses, often located near major highways, and attracting specialized services.
World cities are globally connected urban centers with significant political, economic, and cultural influence. Examples include New York, London, and Tokyo, which promote globalization through the diffusion of goods, services, and ideas. The concept of linkages, or connections between places, is also briefly reviewed.
The differences between a primate city (a city with at least double the population of the next largest city, resulting in concentrated power and opportunities) and the rank-size rule (where the population of a city is inversely proportional to its rank in the urban hierarchy, indicating more distributed services and economic development) are explained.
The gravity model, which predicts interactions between cities based on their size and distance, is revisited. Larger cities or those offering more opportunities tend to attract more interaction, even if they are farther away.
Christaller's Central Place Theory, which explains the distribution of cities, towns, and services, is introduced. Key concepts include 'range' (the maximum distance a consumer will travel for a good or service) and 'threshold' (the minimum population needed for a business to be viable). Specialized goods have a wider range and higher threshold.
The central place theory also illustrates an urban hierarchy from cities down to villages, forming a hexagonal pattern to ensure full market coverage. Cities, with their greater pull factors and larger populations, are fewer and farther apart, while villages are more numerous and closer to larger urban centers due to their smaller service offerings.
This model describes urban expansion in concentric rings around a CBD (Central Business District). The CBD is the oldest part, with density decreasing outwards. Lower-income residents are often found closer to the CBD in transitional zones, while wealthier residents live further out with more dispersed single-family homes.
The Hoyt Sector Model describes urban growth occurring in wedges or sectors, often along transportation routes. Industries locate near these routes for easy transport, influencing the location of residential areas. This model highlights how transportation systems shape urban development.
The Multiple Nuclei Model suggests a more complex spatial layout with multiple centers (nodes) based on different activities and jobs (e.g., airports, malls, universities). Each node attracts specific populations and businesses, demonstrating how specialized areas influence urban structure.
This model, also known as the Peripheral Model, accounts for the impact of cars and highways, featuring a central city surrounded by edge cities and suburban growth. It reflects how modern transportation reduces the CBD's dominance, with businesses and residences decentralizing around beltways.
Informal settlements are residential areas built on land without legal ownership, often lacking basic infrastructure and government regulation. They are particularly prevalent in developing countries due to rapid urban growth, insufficient housing, and high birth rates in Stage 2 of the Demographic Transition Model.
This model incorporates colonial influences, featuring a central plaza and CBD with a spine extending outwards, where wealthier residents and businesses are located. Squatter settlements form on the periphery due to rapid urbanization, while disamenity zones contain areas of extreme poverty.
This model presents three CBDs: a colonial CBD (grid-like), a market zone (informal economy), and a traditional CBD. Ethnic neighborhoods are often divided by roads, and informal settlements ring the city, reflecting the impact of colonialism and rapid population growth.
A unique model without a CBD, centered around a port zone, emphasizing trade and colonial influence. It features a mix of new suburbs and squatter areas, and government zones to oversee commerce.
The density gradient explains that population density decreases from the city center outwards. This is linked to the bid-rent theory, where land is most expensive in the CBD, leading to vertical construction. As distance from the CBD increases, land becomes cheaper, allowing for more dispersed horizontal development.
High-density areas close to the CBD have skyscrapers, traffic, and mixed-land use, promoting walkability. Medium-density areas feature duplexes and smaller apartments. Low-density areas, further from the city, consist of spread-out single-family homes, longer commute times, and higher car dependency.
Urban sustainability aims to meet current needs without compromising future generations. Environmental sustainability focuses on resource management and ecosystem protection, while social sustainability ensures access to healthcare, education, and community spaces for all residents. Economic sustainability promotes equitable economic opportunities.
Zoning refers to government regulations on how land can be used (e.g., commercial, agricultural, residential). It helps separate conflicting land uses, though not all places implement strict zoning laws.
Municipalities represent different levels of government (town, county, state), leading to fragmentation. This can cause inefficiencies and tensions as various entities have differing opinions on urban development and policy implementation.
Mixed-land use integrates different functions (e.g., shops, offices, apartments) in close proximity to encourage walkability. Walkable cities are designed for safe and easy pedestrian access, reducing car dependency, pollution, and fostering community interaction.
Smart growth policies are urban strategies that aim to reduce urban sprawl and protect farmlands by promoting compact, walkable cities with mixed-use development. Transit-oriented development (TOD) specifically focuses on placing housing and businesses near public transportation stops to enhance accessibility and reduce car use.
New urbanism is an urban planning movement focused on creating compact, walkable, and diverse communities through neighborhood design, blending housing types and public spaces. Greenbelts are designated areas of undeveloped land around cities to control sprawl, improve air quality, but can also increase housing prices.
Infilling involves developing unused land within existing city limits to prevent outward expansion and utilize space efficiently. Slow growth cities actively limit new development to control urban growth, while smart cities use technology and data to improve efficiency and quality of life.
Growth boundaries restrict urban expansion, protecting farmland and natural areas. While environmentally beneficial, they can lead to increased housing costs and vertical development due to limited land availability.
Brownfields are abandoned properties, often contaminated by hazardous materials. Redevelopment involves cleaning these sites to make them safe and usable again, contributing to infilling and sustainable urban development.
Post-de facto segregation describes ongoing segregation by race or socioeconomic status without legal enforcement, leading to unequal access to services and resources. Gentrification is the process where wealthier individuals move into and improve urban neighborhoods, increasing property values but often displacing lower-income residents and leading to placelessness.
Redlining was an illegal discriminatory lending practice where banks denied loans to residents of certain neighborhoods, typically minority communities. Its historical effects still contribute to wealth inequality and segregation today, by preventing families from building generational wealth through homeownership.
White flight refers to the movement of white residents from cities to suburbs, often spurred by blockbusting. Blockbusting was a practice where real estate agents would induce panic selling among white homeowners by suggesting that minority groups were moving into the neighborhood, then buying properties at low prices to resell at higher rates to minorities, contributing to segregation.
Environmental injustice highlights the unequal exposure of certain groups (often lower-income or minority communities) to environmental pollutants and hazards. Urban blight describes the decline and deterioration of parts of a city, often due to neglect or economic hardship.
Inclusionary zoning policies encourage developers to incorporate affordable housing options for various socioeconomic statuses within new developments to reduce economic segregation. A city's ecological footprint measures the land and resources used to support its population. Policies like farmland protection and urban growth boundaries can help shrink this footprint.
Urban planners use both qualitative data (subjective opinions from surveys) and quantitative data (objective facts like accident rates or service usage) to make informed decisions about funding, infrastructure, and improving city life.
The presenter concludes the extensive Unit 6 review, acknowledging its length due to the large amount of vocabulary. They remind viewers about upcoming Unit 7 live streams and an exclusive review session for all theories and models.