The contribution of city-scale actions to the overall food system’s environmental impacts
This paper by FCRN member Dana Boyer examines how policy interventions at the city scale can affect three environmental outcomes of food production: greenhouse gas emissions, water use and land use. It uses India’s capital city Delhi as a case study. It sets out to assess the magnitude of city-scale food system actions as compared to certain actions which can be taken beyond the city boundary.
The specific city-scale actions which are examined in the paper include diet change, greater equity in household food consumption, increased urban agriculture, improved cooking fuel and food waste management. The reductions of water and land use, and in greenhouse gas emissions are then compared with the reference ‘trans-boundary’ (outside the city) intervention of reducing food waste along the pre-consumer supply chain.
Lead author Dana Boyer writes:
‘Facilitated through programmes such as the Milan Food Pact, the FAO’s Food for the Cities and the C40s Food System Network, the concerns around urban food systems increasingly receive attention. At the individual city level, municipalities have begun developing objectives and initiatives aimed at addressing a multiplicity of urban food concerns, ranging from improving nutrition, health of diet, food access and equity, environmental sustainability, management of food waste, and increasing local production. With the city embedded in the larger transboundary food system, city-scale food system actions are likely to create changes in the environmental impact both locally and beyond the city boundary.
Our results raise awareness, quantitatively, of the role cities can play in managing food system environmental impacts (in addition to local priorities). The findings also present a methodology to identify which food systems strategies are co-beneficial and where tradeoffs must be considered in terms of water, energy, GHG and other social impacts (like equity).’
This paper develops a methodology for individual cities to use to analyze the in- and trans-boundary water, greenhouse gas (GHG), and land impacts of city-scale food system actions. Applied to Delhi, India, the analysis demonstrates that city-scale action can rival typical food policy interventions that occur at larger scales, although no single city-scale action can rival in all three environmental impacts. In particular, improved food-waste management within the city (7% system-wide GHG reduction) matches the GHG impact of preconsumer trans-boundary food waste reduction. The systems approach is particularly useful in illustrating key trade-offs and co-benefits. For instance, multiple diet shifts that can reduce GHG emissions have trade-offs that increase water and land impacts. Vertical farming technology (VFT) with current applications for fruits and vegetables can provide modest system-wide water (4%) and land reductions (3%), although implementation within the city itself may raise questions of constraints in water-stressed cities, with such a shift in Delhi increasing community-wide direct water use by 16%. Improving the nutrition status for the bottom 50% of the population to the median diet is accompanied by proportionally smaller increases of water, GHG, and land impacts (4%, 9%, and 8%, systemwide): increases that can be offset through simultaneous city-scale actions, e.g., improved food-waste management and VFT.
Boyer, D., & Ramaswami, A. (2017). What is the contribution of city-scale actions to the overall food system’s environmental impacts? Assessing water, GHG, and land impacts of future urban food scenarios. Environmental Science & Technology.
For the full paper, see here.
Asia is Earth's largest and most populous continent. It hosts many densely populated and large cities as well as enormous barely populated regions, which all together host over half of the human population. Agriculture as a source of income is of major importance in the region. In most Asian countries, agriculture is the biggest user of water and in some regions can be responsible for to 90% of total water consumption through irrigation.
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