Assessing the sustainability of China's coastal regions: A perspective on local coupling and telecoupling

The transboundary flow of resource elements has resulted in unprecedented transfers of environmental and social impacts, inevitably influencing a region's environmental carrying capacity and sustainability. Consequently, evaluating the effects of both internal and external resource elements on regional sustainability is crucial for advancing sustainable development. This study distinguishes between internal and external resource elements that support the development of China's coastal areas, based on local coupling and telecoupling theories. It employs the emergy analysis method to assess the degree of dependence of these coastal areas on external resource elements, as well as the environmental loading pressures resulting from both internal and external resource elements and evaluates the sustainability of China's coastal regions. Furthermore, the spatial and temporal evolution characteristics of environmental load pressure were analyzed using the Local Indicators of Spatial Association time path, while the driving forces affecting sustainability were examined through the Logarithmic Mean Divis Index method. The results indicate that social development in China's coastal areas increasingly relies on external resource elements. In Hebei, Liaoning, and Shandong, the environmental load pressure primarily arises from the utilization of internal resources, whereas in Tianjin and Shanghai, it mainly stems from external resources. Overall, the sustainability of China's coastal areas is trending downward. Enhancing emergy intensity, promoting sustainable resource use, and reducing reliance on imported resources can contribute to improved sustainability. Finally, several actionable suggestions are provided.