Exploring symbiotic pathways: Unveiling the evolution and key drivers of China's human-environment relationship

Rapid urbanization increased human demand for natural resources, disrupting the balance between human and environment. This disruption led to regional environmental degradation, frequent natural disasters, and severe challenges in achieving sustainable development goals. In this context, fostering human and environment harmony is essential. However, research on quantifying their relationship and exploring the driving factors and mechanisms at a national fine spatial scale remains insufficient. This study endeavours to address this gap by constructing China's eco-environmental quality index (EQI) and human activity intensity (HAI) evaluation index systems with a 1 km resolution. Furthermore, the study utilizes the four-quadrant model and trend analysis to reveal the human-environment relationship, and employs the Bayesian network model to explore key drivers and underlying mechanisms influencing their relationship, aiming to foster harmonious human-environment interaction. Our results show that: (1) Both EQI and HAI increased over time, with their high values concentrated on the southeast side of the Hu Line but low on the northwest side. (2) The proportions of coordination and running-in areas increased while those of degradation and conflict areas declined, with 36.77% of the regions showing positive synergy during 2000–2020, indicating that China's human-environment relationship tended toward coordination. (3) Bayesian network analysis identified land use intensity, GDP, fraction vegetation coverage, and population density as critical factors affecting human-environment relationship. From a quadrant-based analysis, natural and eco-environmental factors including precipitation, water yield, and net primary productivity mainly influenced the spatial distribution of coordination and running-in intensity, while socioeconomic factors like population density and GDP primarily drove the spatial distribution of degradation and conflict intensity. This study finally proposed tailored management recommendations which would provide scientific support to facilitate the coordination and harmony of regional human-environment relationship.