Spatio-temporal pattern assessment of China's environmental performance and its spatial drivers: evidence from city-level data over 2003-2019.

A comprehensive assessment of China's environmental performance (EP) and an investigation into its driving factors are essential prerequisites for advancing environmental protection efforts. However, existing studies have often exhibited a one-sided EP evaluation approach and lacked a systematic perspective. Consequently, this study has adopted a holistic approach by integrating environmental protection and pollution within the same theoretical framework. We have employed the "P-S-R" model to comprehensively assess the EP of 272 cities from 2003 to 2019. Concurrently, we have applied the spatial Durbin model to analyze EP drivers utilizing three spatial matrices. The findings of this study reveal several vital insights. Firstly, the mean EP value for China is 0.1138, indicating a low level, but it demonstrates a consistent upward trend over the years. When comparing cities with high EP, they are predominantly situated in northern China, northeastern China, and certain areas along the southeastern coast. Secondly, from a spatial perspective, the directionality of EP exhibits a trend from "northeast to the southwest," with the center of gravity located in and around Zhumadian, Henan Province, gradually shifting towards the northeast. The majority of cities fall within the H-H and L-L clusters, displaying significant positive spatial autocorrelation effects. Thirdly, EP drivers encompass a wide range of factors, including economic development, urbanization, resource dependence, industrial structure, infrastructure construction, environmental regulation, government regulatory capacity, scientific and technological innovation, and foreign direct investment. These drivers also exhibit significant spillover effects. Finally, the characteristics of EP development vary between resource-based cities (RBCs) and non-resource-based cities (non-RBCs), as well as among the eastern, central, and western regions. Moreover, there are disparities in the driving factors' direct, indirect, and overall effects. Consequently, we must propose tailored strategies and recommendations to enhance EP, considering the heterogeneous effects of influencing factors across different city types, regions, and collaboration approaches.

The evolution of landscape ecological security in Beijing under the influence of different policies in recent decades.

Urbanization is an important force driving the development of the social, economic, and ecological environments in urban China. As the capital of China, Beijing has experienced a shift in the development process from emphasizing economic development to emphasizing ecological livability in recent decades. During this period, the Olympic Games, real estate development, and environmentally friendly construction policies were major events that affected Beijing's urban ecosystem and its safety. Based on the Pressure-State-Response (P-S-R) framework model, this paper establishes an indicator system for assessing the ecological security of Beijing from 1995 to 2015. The indicators were generated through coupling of an ecological model with time-series multi-source remote sensing data such as night light images and Landsat ETM images. We assessed ecological security during different policy periods and developed an ecological security early warning system for Beijing. After the effects of the economic development policy and the bid for the Olympic Games from 1995 to 2005, the urban area of Beijing with falling ecological security continues to expand. From 2005 to 2010, due to the joint effect of 2008 Olympic venue construction, urban environmental remediation policies, and real estate policies, the overall safety level in the central city was better, but the suburbs showed the opposite trend. In 2010-2015, real estate developed explosively in Beijing, while environmentally friendly development became strongly emphasized and the economic status of the capital weakened. The ecological security of the main urban area began to improve significantly, but the outer urban area and suburban areas were greatly affected by real estate development and exhibited a clear decline in ecological security.