With ever‐growing populations, cities are increasingly interested in ensuring a well‐functioning food system. However, knowledge of variation between individual city food systems is limited. This is particularly true in countries such as India, experiencing significant issues related to food security and sustainability. This paper advances the understanding of urban food systems, by analyzing the unique food systems of nine cities within India, through the integration of multiple city‐specific data sources including demand of residents, visitors and industries, and commodity‐specific supply chains to assess nutrition, environmental impact, and supply risk. This work finds a large degree of intercity food system variability across multiple food system characteristics. Specifically, levels of undernutrition vary, with the percentage of city populations who are underconsuming protein ranging from 0% to 70%, and for calories 0% to 90%. Environmental impacts (consumptive water loss, land use, and greenhouse gas emissions) of urban food demand also show variation, largely influenced by differing composition of residential diet. Greenhouse gas emissions are also largely influenced by location of production and spatially informed energy intensity of irrigation. Supply chain distance (“food‐miles”) also vary by city, with the range of 196 (Pondicherry) to 1,137 (Chennai) km/Mg—shorter than more industrialized nations such as the United States. Evaluating supply chain risk in terms of water scarcity in food‐producing regions that serve city demand finds production locations, on average, to be less water‐scarce than the watersheds local to the urban environments. This suggests water‐intensive agriculture may at times be best located at a distance from urban centers and competing demands.
Supply chain complexity is perceived to exacerbate the supply disruptions or shocks experienced by a city. Here, we calculate two network measures of supply chain complexity based on the relative number—horizontal complexity—and relative strength—vertical complexity—of a city’s suppliers. Using a large dataset of more than 1 million annual supply flows to 69 major cities in the United States for 2012–2015, we show that a trade-off pattern between horizontal and vertical complexity tends to characterize the architecture of urban supply networks. This architecture shapes the resistance of cities to supply chain shocks. We find that a city experiences less intense shocks, on average, as supplier relative diversity (horizontal complexity) increases for more technologically sophisticated products, which may serve as a mechanism for buffering cities against supply chain shocks. These results could help cities anticipate and manage their supply chain risks.
more » « less- NSF-PAR ID:
- 10403875
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- npj Urban Sustainability
- Volume:
- 3
- Issue:
- 1
- ISSN:
- 2661-8001
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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