African Urban Model
Also called the De Blij Model. The influence of European colonization is felt, with about ½ the population living in primate cities - and the world’s fastest-growing cities. The Europeans created prominent urban centers including ports along the coast. The CBD has three districts: a remnant of the colonial CBD, an informal and periodic zone, and a transitional business center where commerce happens along the front of stores.
Bid-Rent Theory
Geographic economic theory refers to how the price and demand for real estate change as the distance toward the Central Business District (CBD) increases.
Blockbusting
As African Americans moved into cities, “white flight” began as whites emigrated from an area in anticipation of blacks immigrating into the area. White flight was encouraged by real estate practices, especially blockbusting and redlining. Blockbusting was the practice of real estate agents to convince white homeowners living near a black area to sell their houses at low prices, convincing them that black families would move in and ruin the neighborhood. The agents then sold the houses at much higher prices to black families. (1950s - 1970s)
Boomburg
A large rapidly growing city that remains essentially suburban in character even as it reaches populations more typical of urban core cities. Ex: Lakewood, CO is known for its rapid growth of expensive housing, with no concern for urban sprawl.
Brownfields/Rustbelt
A brownfield is a property that has the presence or potential to be a hazardous waste, pollutant, or contaminant. Often had a previous industrial use that used hazardous chemicals. A rustbelt is an area previously used by factories and industry, that due to outsourcing, has been abandoned and the region has many brownfields. The term is based on the rusting heavy machinery left behind. Ex. Detroit, Flint, Akron, and Toledo, have been heavily affected by these issues.
Burgess Concentric Zone Model
In 1925, Burgess explained an urban land use model which divided cities into a set of concentric circles expanding from downtown to the suburbs.
Census
a counting of the population, used by government and businesses. A census tract is an area divided up by approximately 5000 residents and corresponds, where possible, to neighborhoods. Ex. The US Census occurs every 10 years, and it is used to ensure the government divides the House of Representatives fairly among all its citizens.
Central Business District
The best known and most visually distinctive area of most cities in the downtown area, known as the Central Business District or CBD. It is compact but contains a large percentage of the public, business, and consumer services. It is the easiest part of the city to reach from the rest of the region. Ex. The CBD includes businesses with a large functional region and businesses like professional sports teams and corporate offices.
Christaller’s Central Place Theory
A central place is a market center for the exchange of goods and services by people attracted from the surrounding area. The central place is so called because it is centrally located to maximize accessibility from the surrounding region. Central places compete against each other to serve as markets for goods and services.
Counter Urbanization
The process by which a significant portion of the population of an urban center starts to migrate away from the city to live in suburbs or rural areas. Ex: As people work on technology, they realized they did not need to at a certain location to work, so they began to move out of cities, and work from home in more rural communities.
Decentralization
The social process in which population and industry move from urban centers to outlying districts. Ex. Moving corporate offices from the CBD to a rising suburb and population follows. This is done to save on land costs.
Disamenity Zones (Zones of Abandonment)
The very poorest parts of cities that in extreme cases are not connected to city services and are controlled by gangs and drugs. Ex. Favelas in Brazil
Edge City
A node of office and retail activities on the edge of a urban area. Part of the Galactic City Model. Begins as a suburb of a city, but when it develops its own CBD, it becomes a city itself. Ex: Outside of Paris, La Defense has become an edge city.
Environmental Injustice
This happens when people are disproportionately impacted by environmental factors because of discrimination. (race-based environmental inequity). Ex. Flint water crisis. Lead pipes were still being used and the source was changed to save money, and the poor (and black) residents of the community were falling sick from lead poisoning and other illnesses.
Ethnic Neighborhood
A place with a high concentration of an ethnic group that is distinct from those in the surrounding area. Ex. Chinatown or Little Italy within New York City or Chicago.
Exurb
The small communities lying beyond the suburbs of a city that are residential, prosperous, but rural. Unlike the farming communities that are nearby.
Farmland Protection Policies
Governmental regulations that try to prevent sprawl and retain farmland. Promotes growth within specific boundaries. Ex. As a city grows, it encroaches on existing farmland. By having local governments create a policy to protect farmland, it cannot be forced to leave and can maintain its initial purpose.
Food Desert
An area that has a substantial amount of low-income residents and has poor access to the grocery store and healthy food choices. Ex: South Los Angeles, home to the Guerrilla Gardener, is a food desert, due to its low socio-economic status and lack of grocery stores that carry healthy food options.
Galactic City Model
Also known as the Peripheral Model. Developed by Chauncey Harris and Edward in 1945, an urban area consists of an inner city surrounded by large suburban residential and service nodes tied together by a beltway or ring road. Rather than an entirely new model, it is a modification of the Multiple Nuclei model, reflecting the growth of suburbs with the nodes of consumer and business services around the beltway called edge cities. Ex. As Draper grows, it is no longer a suburb but has become a center for technology, separate from the Salt Lake City CBD.
Gentrification
Renovating inner city housing to attract middle-class residents. Ex. Buying a home in a run-down neighborhood, remodeling it, and reselling has great value for the investor, but it in turn raises the value of the homes in the neighborhood, leading to unaffordable housing in that neighborhood.
Greenbelts
A green belt is a reserved ring of well-maintained parks circling the urban city center. Ex. Central Park
Harris and Ullman Multiple Nuclei Model
A model of urban land use in which a city grows from several independent points rather than from one central business district. Each point acts as a growth center for a particular kind of land use.
Hoyt Sector Model
In 1939, Homer Hoyt developed the Sector model, stating that a city develops in a series of sectors, not rings. Different areas attract different activities by chance or environmental factors.
Inclusionary Zoning
Municipal and county planning ordinances that require a given share of new construction to be affordable by people with low to moderate incomes. Ex: Designing new neighborhoods to have various types of housing, various lot sizes, so people of varied economic status can live in the same neighborhood.
