Carbon Storage Potential in Urban Parks and Green Corridors: A Review

Urban green spaces (UGS), particularly urban parks and green corridors, are crucial for carbon storage, mitigating climate change, and sustainable urban development. However, quantitative evidence on the carbon storage potential (CSP) in these spaces remains fragmented, limiting their integration into urban planning and policymaking to realize a carbon-efficient green infrastructure network. Following PRISMA guidelines, we synthesize studies from 2010-2024, identified from major databases (e.g., Scopus, Google Scholar, and ScienceDirect), to provide evidence on above-ground biomass in urban parks and green corridors, especially across different climate zones and green space types. The preliminary synthesis reveals significant global variability in CSP among these spaces: urban parks range from 15 to 171 Mg C ha⁻¹, while green corridors, which are much higher due to high tree density and continuous ecological structure, particularly urban forests, can reach 21 to 428 Mg C ha⁻¹. In addition, CSP is strongly influenced by four main factors, including: (i) tree and vegetation characteristics, (ii) ecological-climatic conditions, (iii) urbanization and land use change, and (iv) management practices. Analyzing the influencing factors to take concrete action is crucial to unlocking the full carbon-storage potential of UGSs. This study highlights implications in planning and policy, emphasizing that urban planning and policy can proactively shape the landscape to enhance carbon storage, rather than simply managing existing green assets. In addition, several strategic planning principles can be considered to realize a carbon-efficient green infrastructure network, including: (i) integrating into broader policies such as climate change, spatial planning, and land use management; (ii) optimal planting practices with a focus on connectivity and multifunctionality, and extending the planting of trees. By applying these principles, cities can transform their fragmented green spaces into a purposeful, high-performance green infrastructure network. The study provides comprehensive insights for urban planners, policymakers, and environmental researchers in their efforts to enhance CSP, aiming to achieve carbon neutrality targets and promote a climate-resilient urban environment.