This is a blog post I’m making as both a personal study tool and a potentially beneficial class review. Enjoy!
Urbanization is the demographic shift from rural areas to cities and their outlying urban areas. There are five major global trends regarding this phenomenon that you need to know:
- More people live in urban areas than ever before, and that percentage is rising. From 1850 to 2007, the percent of people living in urban areas skyrocketed from 2% to 50%, and we’re tracking to hit 60% by 2030. Most of this growth is in developing countries’ already stressed cities.
- The number and sizes of urban areas are mushrooming. Each week, 1 million more people join urban areas’ populations. Between 2006 and 2015–a scant six years away–the number of urban areas with at least 1 million people will jump from 400 to 564.
- The urban populations of developing countries are rapidly increasing. By 2030, the percent of people living in developing countries’ urban areas will jump to 56% (from 2007′s 43%), and in South America, 80% of the people already live in urban areas.
- Developed countries’ urban growth is slower than developing countries’ urban growth. Despite this, projections indicate that 84% of developed countries’ populations will live in urban areas by 2030. (compared with 2007′s 75%)
- Poverty is increasingly urbanized. At least one billion people worldwide live in crowded, unsanitary slums and shantytowns or live in cities’ outskirts. This number may double in 30 years.
A poverty-stricken shantytown in Lima, Peru.
Why is poverty becoming urbanized? Well, that’s inextricably tied to the very reasons why people end up in urban areas in the first place. There are factors that pull (attract) people to urban areas, and there are factors that push (force) people to leave rural areas for urban areas.
- Pull factors: jobs, food, housing, entertainment, freedom from religious, racial, and political conflicts
- Push factors: poverty, lack of land for growing food, declining agricultural jobs, famine, war
As more and more people join urban areas, they have to grow, and in some cases, this growth qualifies for urban sprawl, the growth of low-density developments on the edges of cities and towns. These developments result in loosely connected “hodgepodges” of housing developments, office complexes, and commercial centers. Granted, there are some requisites for urban sprawl to occur: affluence, ample and affordable land, automobiles, cheap gasoline, and poor urban planning. Charlotte seems to be suffering from this sort of spreading-out.
An afternoon view of Los Angeles' urban sprawl.
Because everything in urban sprawl is spread out over large swaths of land, there tend to be many problems associated with urban sprawl. I will break them down by category:
- Land and biodiversity: As urban sprawl “gobbles up the countryside,” as our book puts it, it results in the loss of cropland, the loss of forests and grasslands, the loss of wetlands, and the loss and fragmentation of wildlife habitats.
- Water: With more people comes an increased need for water, and this translates into an increased use of surface water and groundwater. Due to clear-cutting wide swaths of vegetation–and the subsequent loss of root systems–there is increased runoff and flooding. All of those people produce all sorts of pollutants, which lead to increased surface water and groundwater pollution, the most undesirable one being sewage; moreover, the growing numbers of people decrease natural sewage treatment.
- Energy, Air, and Climate: Urban sprawl tends to result in nonexistent or inadequate mass transportation systems, and people are consequently wedded to their automobiles, leading to increased air pollution, increased greenhouse gas emissions, and enhanced global warming. The increased demand for energy skyrockets energy production–leading to the aforementioned effects–and energy waste also rises due to low population density.
- Economy: As people leave the city to the suburbs–the classic urban sprawl scenario–much of the city’s tax base leaves with them, leading to higher taxes, increased unemployment in the central city, and the decline of downtown business districts.
Please keep in mind, however, that urban sprawl is the excessive end of the spectrum of urbanization; as a whole, urbanization much more of a mixed bag, with both pros and cons.
Pros: centers of economic innovation; educational and technological leaders; better access to medical care and family planning; recycling is more economically feasible; helps preserve biodiversity by concentrating people in cities and reducing stresses on wildlife habitats
Cons: unsustainable ecological footprints (urban areas are 2% of land area but consume 75% of its resources); lack of vegetation (shade, oxygen, absorb air pollutants, cooler temps.); huge use of water; produce most pollution (and is concentrated); increased spread of infectious disease, especially if adequate drinking water and sewage systems are not available; “heat island” effect; light pollution
Cities are constantly trying to tackle these problems, and one of the most pressing is the one of transportation and its effects on the city’s well-being. In many ways, city growth somewhat hinges on transportation: in compact cities (build “up”) like Tokyo, people build up and walk, ride bicycles, or use mass transit; in places like the United States, however, the spread-out, built-for-the-car dispersed city (build “out”) is the more prevalent type. There seems to be a pattern with transportation, though; as efficiency increases, the need for scheduling also increases, and this scheduling is something into which people must buy. Bicycles do not necessarily fit this mold–indeed, they may be one of the most efficient means of personal transportation–but their size, small range, and lack of weather protection makes them suited only for some conditions.
There is a way our book mentions, however, in which we can create and maintain sustainable cities: smart growth. Smart growth calls for more environmentally sustainable development by lessening dependence on cars, controlling and directing sprawl, and reducing wasteful resource use. This can be accomplished by limits/regulations, protection, zoning, taxes, planning, tax breaks, and revitalization for new growth.
An ecocity is essentially a more environmentally sustainable city than the one smart growth attempts to address, for it emphasizes these six sustainability goals:
- Build/re-design cities for people, not cars
- Use solar and other locally available renewable energy resources; design buildings to be heated and cooled as much as possible by nature
- Use energy and matter resources efficiently
- Prevent pollution and reduce waste
- Recycle, reuse, and compost at least 60% of all municipal solid waste
- Protect and encourage biodiversity by preserving surrounding land and protecting/restoring natural systems and wetlands
A picture of Curitiba, Brazil, our book's model environmentally sustainable city. Note the greater abundance of trees here than in Los Angeles.
- Lima: http://www.responsibletravel.com/community/images/member/f_51602718_3196.jpg
- LA: http://www.photodiary.org/large/e_1167.jpg
- Curitiba: http://www.freewebs.com/filipebruno/curitiba.jpg