Source: Earth PD http://bit.ly/1JPJLLL Suburbia CC http://bit.ly/1A67iaq Utah CC http://bit.ly/1zPtjH3
Hi. I'm Jensen Morgan. We're going to talk about some great concepts in environmental science. Today's topic is urban sprawl. So let's get started.
Urban sprawl is the expansion of urban areas onto undeveloped or agricultural land. Today, we're going to talk about historical change in land use in the US in relation to urban sprawl. We'll explore the impacts and consequences of urban sprawl, as well as a historical example.
In the early 1900s, before the automobile had really taken hold and shaped policies and regulations, different land uses were more integrated and less defined by car and truck transportation. After the economic explosion following World War II, US middle and upper class began moving to suburbs on the outskirts of cities to find more affordable housing. This process of moving to suburbs continued and grew after the Vietnam War, as well. This transition was facilitated by government subsidies on roads and gasoline.
By the 1970s, Federal government began taking the lead and responsibility on many national environmental issues. However, land use determination remained largely in the hands of local governments. Moving into the 1990s, interest and concern in urban sprawl issues increased, largely due to abandonment of certain inner city areas. This was compounded by Vice President Al Gore's interest and awareness of urban sprawl problems.
Urban sprawl consumes more than one million acres per year or two acres per minute for development. Urban sprawl also takes a toll on air quality, because it requires more vehicle miles to be traveled to get to work or other locations, while limiting public transport and the ability to bike or walk. The result is more emissions such as nitrogen oxides and ground level ozone and more time spent in cars, which increases exposure to potential carcinogens present in vehicles.
Habitat fragmentation can also result from urban sprawl and has a number of negative effects, such as threatening species, reducing biodiversity, increasing potential for infectious diseases, and increasing watershed pollution from impervious surfaces. Low population density only encourages and increases these impacts, because it requires more land be developed.
Some additional byproducts of urban sprawl include, the loss of farmland, which affects diversity and cost of food, decreased social equity, as poverty is concentrated, increased crime in now abandoned and under-populated inner city areas, lowered walkability of cities, which encourages obesity and health problems, increased dependence on foreign fuels, because more is needed for extra vehicle miles traveled, and decreased civic engagement, as populations are spread out and isolated from each other.
A historical example of this is the state of Utah. Utah, as of 2014, had the second fastest urban sprawl growth rate in the United States. Utah's zoning laws encourage development designations, which facilitates urban sprawl. Between 2002 and 2010, urban expansion grew 17.6%, consuming 203 square miles of agricultural or undeveloped land. Across the country, in that same time period, 13,000 square miles, or an area larger than the state of Maryland, underwent the same transition.
Now, let's have a recap. Today, we talked about the history of urban sprawl in the United States since the early 1900s, its impacts and additional consequences, as well as the state of Utah, which had the second fastest urban growth rate in the country. Well, that's all for this tutorial. I hope these concepts have been helpful, and I look forward to next time. Bye