Elisa Addlesperger’s map, created as part of a final project for GEO 243 Remote Sensing, shows the impact of development on availability of farmland in four collar counties in northeastern Illinois: Kane, Kendall, Will and McHenry. Landsat 5 multi-band spectral images from 1987 and 2007 were processed to create classes showing development density in each respective year. Open or agricultural land is indicated with a bright green. Based on this visual analysis, substantial amounts of arable land have been lost to development in Chicago’s collar counties. According to the state Department of Agriculture, Illinois has lost over 3.6 million acres of farmland since 1950, an average of almost 77,000 acres each year.* Much of this loss is due to expansion of the greater Chicago metropolitan area from older suburbs to a new ring of development, sometimes referred to as “exurbs.” Although a consistent definition of the term has yet to become standard, researchers tend to agree on general characteristics: exurbs are located beyond traditional suburbs established in the latter half of the 20th century, and are characterized by low-density, fast-paced development. Causes of exurban sprawl are complex, and cannot be entirely attributed to an increase in regional population. Economic pressures incentivize farmers to sell land for equity, while the relatively cheaper price of land in the exurbs fuels development. Loss of agricultural land to low-density development has a net negative impact on the environment through reduction of groundwater quality and a loss of habitat for native plant and animal species.
*Illinois Department of Agriculture. (2001). Farmland Protection.
urban, sprawl, environment, density, suburbs, USA