Carbon emission reduction potential assessment in food transportation by urban agriculture: A case study of main urban area of Nanjing, China.

As an emerging urban green infrastructure and continuous productive urban landscape, urban agriculture can increase the resilience of urban food systems and reduce carbon emission in food transportation. However, there are few studies in China on the potential of urban agriculture and its role in carbon emission reduction. With semantic segmentation and spatial analysis method to identify urban agricultural potential spaces on the ground and rooftops based on satellite images and Lidar point cloud data in the main urban area of Nanjing, we estimated their potential in vegetable production and the CO emission reduction effect in food transportation. The results showed that there were 2904.39 hm of ground and 2976.96 hm of rooftops in the study area with the potential to be used for urban agriculture. Under a scenario with 80% potential space utilization, it could produce approximately 225000 t of vegetables per year, which equated to 43.6% of annual vegetable consumption in the study area. Meanwhile, it would reduce CO emission in long distance food transportation by 63700 t per year.