How did Yundang Lake in Xiamen transform from polluted water to a habitat for egrets?

Nearly 90 bird species now inhabit the urban wetlands near Yundang Lake in Xiamen. It's hard to believe that the lake was filled with sewage 36 years ago. Since the 1980s, local authorities have implemented proactive measures to promote sustainable development. Watch the video to discover how Xiamen has transformed the ecological environment of the lake. #China #Xiamen #ecologicalprotection