Research Progress and Planning Strategies on Urban Blue-Green Infrastructure for Increasing Carbon Sequestration and Decreasing Carbon Emissions

Objective The world is still in a phase of rapid industrialization and urbanization, characterized by a high degree of concentration and intense consumption of energy and resources. Carbon overshoot has become the primary root cause of various environmental problems in cities and globally, further impacting human physiological and psychological health. Cities are the largest sources of carbon emissions and are crucial regions for achieving carbon neutrality goals. Urban Blue-Green Infrastructure (UBGI), comprising natural, semi-natural, or artificial green and blue spaces within cities, is considered the only carbon sink in urban areas and has increasingly attracted widespread attention from researchers. However, there are still many unresolved issues regarding the effectiveness of UBGI in carbon sequestration and emission reduction: 1) How is the energy efficiency of carbon sequestration and emission reduction measured and what factors influence it? 2) What are the mechanisms and pathways through which UBGI sequesters carbon and reduces emissions? 3) How can UBGI be regulated at multiple scales to enhance its effectiveness? 4) What are the limitations and potential directions for development in current research? This study aims to address these questions and propose scientifically sound planning strategies for the construction of UBGI to achieve urban carbon neutrality goals.