Regional industrial synergy: Potential and path crossing the "environmental mountain"

Regional cooperation and common development are the new normal strategies of regional sustainable development and important approaches that positively affect economic globalization. Breaking the "small island thinking" model of a region or a country that only relies on "self-development" in economic development, exploring new kinetic energy for regional economic growth, and tapping the new potential of coupling development of economy and environment are important tasks to promote regional coordinated development. Benefits of regional industrial synergy in terms of economic growth, energy conservation, and consumption reduction are discussed on the basis of the synergetic development of regional industries as the entry point. Modified spatial gravity model, location quotient (LQ), LQ ratio (LQR), Krugman regional division index, industrial structure similarity coefficient (S), time series analysis, and scenario analysis are applied. In addition, the "Xia-Zhang-Quan" Metropolitan Area is considered as a case. Results show that: (1) the three industrial development of Xiamen, Quanzhou, and Zhangzhou has evident gradient structure, but the industrial structure has serious isomorphism (S_xq = 0.94, S_xz = 0.96, S_qz = 0.98); (2) Xiamen and Zhangzhou can achieve synergetic development through intra-industry and industrial chain division (LQR_xz = 1.214), and Xiamen and Quanzhou can further cooperate on inter-industry division (LQR_xq = 0.566); (3) In 2025, compared with the unadjusted mode, the "Xia-Zhang-Quan" Metropolitan Area can achieve 35.21% of economic growth space and reduce energy consumption by 32.85% under the synergetic mode. Therefore, regional industrial synergy can not only release great economic growth potential, but also has important potential in promoting regional development to cross the "environmental mountain". This study aims to explore an effective regional synergetic development path and new driving forces to promote developing countries, especially China, to cross the "environmental mountain" and realize the coupling development of social economy, resources, and environment.