The establishment of Chinese ecological conservation redline and insights into improving international protected areas.

China proposed the Ecological Conservation Redline (ECR) strategy in 2011 and listed it as an important part of the ecological promotion process in 2013. In 2017, China implemented the designation of ECR at a national scale. The aim was to demarcate areas with unique ecological functions. Therefore, the ECR became a key part of national ecological security. Three major types of area are covered by the ECR so that important ecosystem functions can be protected. These are ecologically fragile zones, biodiversity, and natural landscapes. The ECR is characterized as being fundamental, systematic, and mandatory. This study summarizes the developmental background, theoretical framework, and structural composition of ECR, and highlights recent advances. A comparison of the ECR to international protected areas showed that they were generally similar, but there were differences in the methods used to protect targets, their system design, and their management, which provided insights and recommendations that could improve the construction and management of protected areas in the future. These included: (1) increasing the integrity of ecological protection by replacing dispersed protection with a more comprehensive and systematic approach, (2) increasing the spatial accuracy of protection to enhance the effectiveness of protection, and (3) implementing an overall-process management to guarantee the sustainability of protection. Finally, suggestions are made for further protected area improvements and ecological protection, including further theoretical exploration, strengthening management, and facilitating international cooperation.