What is in this article?:
- Many urban centers initially grew among particularly fertile soils so farmland near these areas tends to be quite productive.
- Farms near urban areas have greater access to markets and ports and therefore lower transportation costs.
- As a result, these farms may generate economic profits above comparable lands further from the urban center.
Urban influence alters land use patterns
One of the primary drivers of farmland values near the urban fringe is the potential for conversion to residential or commercial use. Throughout recent decades, a number of U.S. cities have expanded through what is generally referred to as "urban sprawl." Irwin and Bockstael (2007) show that urban sprawl alters, not only the value of land, but the pattern of land use activities. The authors demonstrate that land parcels near the urban fringe are more likely to be divided into smaller pieces and surrounded by other land uses, or fragmented. The degree of fragmentation rises and then falls as distance from the urban center increases. That is, at the urban core, one observes large continuous patterns of urban land use activities, such as commercial and residential areas, yet at the urban fringe, land uses are divided into smaller patches which may consist of residential, commercial, industrial, and natural resource based activities, including agricultural production. Past the urban fringe, agriculture becomes the dominating land use activity. This pattern of development effects agricultural production practices, as well as the quantity and quality of nonmonetary benefits of agricultural land use (Barnard, 2000).
Figure 5 shows the fragmentation of agricultural lands at the urban fringe of the four selected metropolitan areas. The fragmentation measure is calculated through geographic imaging systems (GIS) using the 2006 National Land Cover Database. The fragmentation measure examines the size and shape of contiguous agricultural parcels. Highly fragmented parcels are shown in dark green. The greatest degree of spatial fragmentation occurs in the Atlanta metropolitan area, and the urban fringe near Chicago exhibits the least pronounced fragmentation. Part of this difference may be attributed to the nature of the agricultural production in the surrounding areas. The area around Atlanta contains a greater proportion of specialty crops and poultry which can be profitably raised on smaller tracts, yet near Chicago larger tracts of land are required for row crop production. However, similar crops are grown near Minneapolis which exhibits a higher degree of fragmentation. The difference between Chicago and Minneapolis, therefore, may be more directly attributable to differences in urban characteristics.
It is also important to note that land use patterns are not symmetric around the urban core. Thus, even within a particular metropolitan area, the degree of urban influence is not uniform across space. For example, the degree of fragmentation is greater west of Dallas than east.