Evaluation and dynamic evolution of eco-efficiency of resource-based cities is of great significance for ecological restoration, industrial transformation and sustainable development of resource-based cities. Based on the data of 40 resource-based cities from 2012 to 2017, we first study eco-efficiency of resource-based cities from both static and dynamic aspects by super-efficiency DEA and the Malmquist index. Additionally, then, we analyze its dynamic evolution trend by Kernel density estimation. The main results are as follows: First, the eco-efficiency shows a steady growth trend; growing cities are the highest, followed by regenerative cities and mature cities, declining cities are the lowest. Second, technological progress has the greatest contribution to growth of eco-efficiency, and scale efficiency restricts its growth. Third, efficiency distribution of resource-based cities with different life cycles show different characteristics of evolution, and the regional gap is narrowing gradually. Finally, management implications are put forward based on the empirical conclusions.

Although there are frequent floods, the need of utilizing the flood-water resource in Yangtze River is becoming increasingly intense. Following the concept of ensuring health Yangtze River and promoting harmony between people and water, the Three Gorges Reservoir is practiced as an example for utilization of floodwater resource based on accurate hydrological forecast and moderately taking the flood control risks.