The abrupt onset of the COVID-19 pandemic in late 2019 significantly disrupted China’s domestic agricultural production and supply chain stability. Local governments, responding to urgent circumstances, implemented various trade restrictions that profoundly affected regional economic development. This study, covering data from 2010 to 2019 across 31 provinces, investigates agricultural market integration and regional economic development. Employing a dynamic spatial panel Durbin model, it systematically analyzes the complex relationship between these variables. International trade variables related to agricultural products are then introduced to examine their “substitution effect” in promoting regional economic development through agricultural market integration. The research findings are summarized as follows: (1) disregarding international agricultural trade, a one-unit increase in the agricultural market integration index corresponds to a 0.156% rise in regional economic development. (2) In an open economy, the substitution coefficients for agricultural imports, exports, and total trade concerning market integration are −0.00097, −0.0012, and −0.0038, respectively. (3) The strength of the substitution effect from the international agricultural market to the domestic market varies regionally, with coefficients of −0.00099 and −0.00217 for the eastern and western regions, respectively.

Improving energy efficiency is not only the key to achieving energy conservation, carbon reduction and green development, but also the way to promote the high-quality development of China’s economy. This article measures the total factor energy efficiency (TFEE) of Chinese cities and uses the Energy Rights Trading Pilot Policy (ERTP) as a quasi-natural experiment to evaluate the impact of this market-based environmental regulation policy on TFEE using a difference in differences (DID) model. The results show that ERTP can significantly promote the improvement of TFEE in Chinese cities. This effect is more obvious in coastal cities, high-grade cities and resource-based cities. ERTP can promote the upgrading of industrial structure and enhance the ability of green technology innovation, thereby promoting the improvement of TFEE. ERTP has a negative spatial spillover effect on the TFEE of neighboring regions. This article not only provides empirical support for revealing the complex effects of market incentive based environmental regulation in developing economies, but also provides important theoretical references and practical inspirations for the nationwide promotion and differentiated policy design of ERTP.