Tuesday, February 14, 2017

Philadelphia Food Mapping

GIS Mapping systems can be used in many instances to provide visual representation of collected data and statistics. In the case of Local Food practices in Philadelphia, GIS produced a variety of maps that helped researchers discover abundant amounts of urban land that can be used for food production. First, to understand the social and economic components researchers interviewed a number of people such as urban farmers, farmer’s market owners, and independent retailers. They did this to learn more about the local food systems and the steps that the produce goes through before retail and consumption. This data was then translated into a GIS system called the Select by Location Tool. 

Figure 2 shows the resulting map of this information. Through this tool, the researchers discovered that 50% of community gardens are located within the lowest level income areas in the city. On the other hand, 53% of Farmer’s Markets are located within the higher median income neighborhoods. Next, the research team revealed where the produce comes from, calling this the “food miles”. Using the Point Distance tool, they found that on average the food traveled a total distance of 61 miles before arriving to the markets. In addition, they found out that most of the food was produced Northwest of the city in the rural, mostly Amish country. The food miles on this product were much higher than those that came from urban farms, where most of the traveled distance was less than 10 miles. 

The bar graph on Figure 5 displays that where there is a higher number of farms, there is more food miles on the products.

 Lastly, the researchers used GIS techniques to show the urban food production potential in Philadelphia. They did this using color infra-red aerial photography showing the grassy backyard areas that were suitable for food production. The data was classified into five more specific groups including trees, shrubs, grass, bare soil, and impervious substances. Overlaying the classifications and the photos they created Figure 9, using the N-D visualizer tool. By using GIS, the team was able to show the urban food production in Philadelphia, and formulate a plan to increase the potential of this system.

Kremer, P., & DeLiberty, T. L. (2011). Local food practices and growing potential: Mapping the case of Philadelphia. Applied Geography31(4), 1252-1261.


  1. I would be curious to know what a location map and the point distance tool to find the relationship between locations and distance for an area that is more familiar to us students at SU, such as Houston or DFW or Austin. Because they are heavily populated areas, I would imagine the distance would be longer due to how the cities have expanded.

  2. This could be a cool idea to use for tourism to show where cities have the most dense places for restaurants, outings, and activities.