Urban carbon-sink enhancement strategies: a case study of the carbon-neutral square

In the context of China’s nationwide efforts to achieve carbon neutrality across various industries, traditional squares can no longer fully meet public needs, making ‘ecological sustainability’ the central theme of square development in the new era. This paper, adhering to the balanced relationship among ‘carbon reduction’, ‘carbon sink enhancement’, and ‘livelihood improvement’ first, discusses the fundamental principles of carbon-neutral square construction, followed by an examination of low-carbon management methodologies for such squares, and concludes with an analysis of carbon offset mechanisms (including basic requirements, types of carbon offsets, and accounting methods). Quantitatively, the live-biomass sink exhibits a pronounced sigmoidal trajectory, increasing from 17 t CO₂e at commissioning to ~2296 t CO₂e by 2080, with peak annual uptake of 65 t CO₂e year−1 in 2037–2038. The work constructs a life-cycle standard system for carbon-neutral city squares—a management and technical framework that clarifies the concept and characteristics of carbon-neutral public spaces, informs municipal roadmaps to carbon neutrality, and supports low-carbon building standards.