Research on evaluation and influencing mechanism of ecosystem health in China’s urban agglomerations

• A framework based on EH for the optimization of territorial spatial pattern; • Analyzing the effect mechanism of EH in urban agglomeration areas under carbon neutrality goals; • Identifying four types of territorial spatial pattern optimization zones oriented towards carbon neutrality. Dynamically measuring the impact of human activity intensity on ecosystem health in the context of carbon neutrality is crucial for achieving high-quality development of urban agglomerations’ spatial layout. Currently, lack of study identifying the key factors influencing ecosystem health (EH) under carbon neutrality goals. This study focuses on typical urban agglomerations of China, revealing the spatiotemporal characteristics of EH through a comprehensive “absorption-resistance-recovery” framework. A structural equation model (SEM) was employed to discuss and examine the effect mechanisms of EH in the context of carbon neutrality. The results indicated that from 2000 to 2020, the EH significantly improved in terms of absorption, resistance, and recovery capacities. Absorption increased from 0.27 to 0.33, resistance from 0.53 to 0.64, and recovery from 0.66 to 0.69. The spatial distribution of EH exhibited distinct regional differences, showing an increasing trend from north to south. Southern urban agglomerations such as BG-UA and PRD-UA demonstrated significantly higher EH than northern ones. SEM results revealed that low-carbon policy, green innovation, natural environment, economic and social development, and energy consumption structure have significant direct and indirect effects on EH. The impact of the natural environment on EH gradually weakened over time, with path coefficients of 0.50, 0.42, and 0.07 in 2000, 2010, and 2020, indicating that human activities have become the primary driver shaping urban agglomeration ecosystems under the impetus of urbanization. Additionally, the negative impacts of human factors gradually weakened, reflecting progress in China’s economic transformation and energy structure optimization. The impact of low-carbon policy strengthened significantly, with path coefficients of 0.20, 0.06, and 0.27 in 2000, 2010, and 2020, highlighting the effectiveness of China’s ecological and environmental policies in enhancing EH. This study has provided scientific basis and decision support for formulating differentiated regional ecological policies, promoting sustainable urban development, and achieving national carbon neutrality objectives.