The development of regional industry in China has become one of the significant factors affecting energy efficiency. This paper combined the industry agglomeration theory and the improved Stochastic Impacts model to explore the impact mechanism of producer service industry agglomeration on energy efficiency. We applied spatial econometric model to estimate the spatial effects of the agglomeration on energy efficiency with panel data of 31 provinces from 2008 to 2017 in China. The results showed that China’s inter-provincial energy efficiency has a significant spatial spillover effect. Simultaneously, the specialized agglomeration and diversified agglomeration of producer services have a “U”-shaped effect on energy efficiency. Finally, we need to pay attention to the coordination and synchronization of the specialized agglomeration and diversified agglomeration of the producer service industry. An increase in the relative gap between the two can inhibit energy efficiency, but its inhibitory effect gradually weakened.

River basin cities are areas with remarkable conflicts between the human activity and the ecological environment. They are also important targets for policy implementation of sustainable and high-quality development (HD) in various countries around the world. This article exploits the panel data of 99 cities located in the Yellow River Basin (YRB) from 2006 to 2019 to empirically analyze the spatial effect of financial growth on HD. Spatial weights participated econometric models are utilized to analyze this spatial effect. Empirical results reveal that: (1) the HD in the YRB shows a strong positive spatial autocorrelation. (2) Financial growth exerts an N-shaped curve effect on the HD from a long-term perspective. When this influence spills out to the surroundings, it exhibits an inverted U-shaped characteristic. (3) Green innovation can be an important intermediary factor in the influence of financial growth on HD. (4) The influence of financial growth on HD appears stronger in regions with higher economic levels, where N-shaped effects can be transmitted to the surrounding regions. However, the backward economic development in low-economy regions prevents the spatial spillover of N-shaped effects. This study can be instrumental for countries to formulate financial policies that aim to promote HD in river basin cities.