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·         1924, Ernest Burgessbased on his observarion of Chicago he planned this model

·         urban residents naturally sort themeselves into appropriate rings depending on cultural and class assimilation

·         zone A: central business district

·         zone B: transition à industry and poorer quality

·         zone C: working class

·         zone D: newer and larger houses and buildings

·         zone E: residential suburbs

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·         grid models: land is divided by streets intersect at right angles, forming a grid

·         it’s more common int he US than in Europe

·         advantages: developers can subdivide and auction off large parcels of land

·         disadvanatges: they can be dangerous because they allow a faster car- traffic (because of the straight roads)

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The very first cities were founded in Mesopotamia after the Neolithic Revolution, around 7500 BCE.

Agriculture is believed to be a pre-requisite for cities, which help preserve surplus production and create economies of scale.

Cities reduced transport costs for goods, people, and ideas by bringing them all together in one spot.

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Different agencies and individuals define urban in different ways, but the U.S. Census Bureau ‘s definitions are considered standard.

The U.S. Census Bureau defines “urban areas” as areas with a population density of at least 1,000 people per square mile and at least 2,500 total people.

As of December, 2010, about 82% of the population of the United States lived within the boundaries of urbanization

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- suburbanization is driven by white flight
-describes:  suburbanization and the large-scale migration of whites
-blacks had to move to suburbs
-difficult  to get the mortgages (for blacks)
- communities used restrictive housing covenants to exclude minorities
- White flight contributed to the draining of cities’ tax bases
- exacerbating urban decay caused in part by the loss of industrial and manufacturing jobs as they moved into rural areas or overseas where labor was cheaper
- newest waves of suburbanization: ethnic balkanization

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The rural rebound refers to the movement away from cities to rural and suburban areas.  In the most developed countries many cities are now beginning to lose population.  In the United States in the 1970s, that the rural population was actually growing faster than urban populations. In the last 50 years, about 370 cities worldwide with more than 100,000 residents have undergone population losses of more than 10%, and more than 25% of the depopulating cities are in the United States.  Rather than moving to rural areas, most participants in the so-called the rural rebound migrated into new, rapidly growing suburbs. The rural rebound, then, may be more evidence of the importance of suburbanization as a new urban form in the most developed countries.

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-  In the developing world, huge cities with  slums have developed as agriculture and rural occupations have been supplanted by mechanized industries
- Dhaka , capital of Bangladesh-

15 million people live there  - each new decade the population double

- 80% of the Earth's population live in cities - many of them in exploding slums
- Atig Rahman- "half of the population of the developing world will be in the urban centers within the next decade"
- water shortages
- high buildings - world of the slums

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- industrial era, cities grew rapidly and became centers of population and production
-  18th :century huge numbers of migrants from rural communities into urban areas
- 21st :century, has risen to nearly 50%
- industrial-era cities were rife with dangers to health and safety
- contaminated water and air, and communicable diseases
- Disease often spread through contaminated water supplies
- 19th century : improved with better sanitation,  the greatest killer in the cities was tuberculosis

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Economic and Environmental Effects of Urbanization

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Economic and Environmental Effects of Urbanization

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Urbanization ..

- can force original residents to move to less-desirable neighborhoods
-  has economic and environmental effects
-  is generally a product of modernization and industrialization.
-may be driven by local and global economic and social changes
-pushing up prices :  land prices rise  -gentrification
-growing cities alter the environment
-"heat islands"
 -urban areas replace and reduce the amount of land covered by vegetation or open soil
- evaporation --> cooling
- additional city heat is given off by vehicles and factories
- 2 to 10 degrees Fahrenheit (or 1 to 6 degrees Celsius)

gentrification: A shift in an urban community toward wealthier residents and/or businesses and increasing property values; often resulting in poorer residents being displaced by wealthier newcomers.

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- here is insufficient evidence to assert what conditions gave rise to the first cities, but some theorists have speculated on what they consider pre-conditions and basic mechanisms that could explain the rise of cities
- agriculture is believed to be a pre-requisite for cities
- the advent of farming encouraged hunter-gatherers to abandon nomadic lifestyles and settle near others who lived by agricultural production
- agriculture yielded more food, which made denser human populations possible, thereby supporting city development
- farming led to dense, settled populations

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-political entity
-varied political forms
- some cities had their own legislatures
- no other lord than the emperor
- In Italy, medieval communes had a state-like power
-in exeptional cases cities became  powerful states
- considerable autonomy
- cities offered a newfound freedom from rural obligations
- “City air makes you free”