Selecting and operationalizing indicators for a comparative sustainability assessment of urban agriculture on the example of vertical farming and community supported agriculture

Abstract Intensifying social-ecological urban challenges such as climate change, biodiversity loss and social injustices call for sustainable nature-based solutions. In this regard, bringing food production back into cities can be a major lever. However, so far a systematic comparison is lacking between the environmental, social, and economic sustainability of different types of urban agriculture. This paper addresses this research gap and adds to current sustainability research conceptually as well as empirically. Conceptually, we provide a structured workbook for how to select and operationalize indicators according to their feasibility and suitability for a comparative sustainability assessment of urban agriculture types. Empirically, the indicators have been exemplified in a comparative evaluation of community supported agriculture (CSA) and vertical farming. Based on a qualitative content analysis of its vision guidelines, the results suggest that CSA can be considered the more sustainable form of urban agriculture across all three sustainability dimensions. However, when taking into account that the major benefit of vertical farming in an urban context is its increase in food production efficiency, we suggest balancing its shortcomings and lack of vision on social justice, biodiversity conservation, and food quality by fostering a hybrid model of community supported vertical farming.