Challenges and future perspectives on the ecological uses of reclaimed water

Ecological use is a paramount and primary application of reclaimed water. It is of great significance in alleviating the contradiction between water supply and demand, reducing water pollution, and restoring and maintaining urban water ecosystems. However, the quality and ecological impacts of reclaimed water continue to pose challenges that may create potential ecological and health risks and hinder its long-term sustainable application. This paper examines the entire process of the ecological use of reclaimed water from water recharge to ecological buffer zones to receiving water bodies and addresses the key challenges and future perspectives on the ecological use of reclaimed water. Some strategies, such as establishing a comprehensive evaluation framework, developing ecological safety thresholds of key risk factors in reclaimed water, strengthening the functions of the ecological buffer zone, and optimizing ecosystem service value and the benefit of reclaimed water, have been put forward toward future safe and sustainable ecological use.