Eating food from my backyard: The role of urban and peri-urban agriculture in greenhouse gas reduction

The global rise in human population has substantially increased reliance on agricultural landscapes to meet food security demands. At the same time, conventional rural agriculture is a major contributor to global anthropogenic greenhouse gas (GHG) emissions. Climate change, coupled with the increasing frequency and intensity of extreme weather events, has intensified pressure to develop more sustainable, resilient, and environmentally friendly agrifood systems. Over recent decades, urban and peri-urban agriculture (UPA) has gained increasing attention as a potential strategy to supply food to growing urban populations while delivering a range of environmental, social, and economic co-benefits. Despite growing scientific and policy interest, multiple meta-analyses indicate that the environmental impacts of UPA systems remain poorly quantified, particularly with respect to their contributions to GHG emissions and their potential role in achieving net-zero climate targets. Evidence regarding the GHG mitigation potential of UPA systems remains mixed. Some studies highlight reductions in emissions due to shorter rural-to-urban supply chains (“food miles”) and enhanced carbon sequestration associated with increased urban green space. In contrast, other studies report substantially higher carbon dioxide (CO₂) emissions per unit of food produced in urban agricultural systems compared to conventional rural agriculture. Here, we synthesize insights from an extensive global literature review of UPA systems with the objectives of: (1) clarifying key definitions and characteristics of UPA systems across spatial and temporal scales; (2) quantifying their reported global environmental impacts, such as effects on GHG emissions; (3) identifying the major vegetation types cultivated and assessed within UPA systems; and (4) evaluating existing research and knowledge gaps in process-based crop simulation models and life cycle assessment (LCA) approaches used to estimate food production and GHG emissions in UPA contexts. This synthesis aims to advance understanding of the carbon footprint reduction potential of UPA systems and their interactions with climatic, social, political, and economic drivers, while informing strategies to strengthen their role as effective nature-based solutions within sustainable urban food systems.