Abstract
Beijing, Tianjin, Hebei, Shandong, and Henan (BTHSH) represent a major urban and economic hub in China, with significant implications for environmental protection. This study utilizes the remote sensing ecological index (RSEI) derived from Landsat imagery, with data spanning from 1985 to 2020 at five-year intervals, to evaluate spatiotemporal variations in eco-environmental quality across different phases of urbanization. The Geographical Detector, integrating natural, socio-economic, and nighttime light data, was used to analyze the driving factors and their interactions. Results indicate a general decline in areas with moderate to excellent eco-environment quality, from 90.44% in 1985 to 83.06% in 2020. Urbanization and socio-economic factors have increasingly influenced environmental degradation, particularly in coastal cities. The spatial distribution of eco-environmental quality became more directional after 2011, with a marked decrease in spatial autocorrelation. The predicted improvement regions in eco-environmental quality, based on the combination of the Theil-Sen and Hurst index methods, corresponds to an area percentage of 16.48% in Beijing, 12.6% in Tianjin, 13.08% in Shandong, 22.09% in Hebei, and 23.93% in Henan, respectively. During the rapid urbanization phase (1985-2010), the primary drivers of eco-environmental quality evolution were natural factors. However, in the quality development phase (2010-2020), the interaction between natural factors and socio-economic factors increasingly influenced eco-environmental quality. Identifying the spatiotemporal heterogeneity of eco-environmental quality distribution and its driving factors across different stages of urbanization is of significant theoretical and practical importance for enhancing the ability of urban ecosystems to respond to urbanization risks and achieve sustainable development.