August 15 marks China's National Ecology Day. The country designated the day last year to enhance public awareness and actions to protect the ecological environment.

On August 15, 2005, Chinese President Xi Jinping, then secretary of the Zhejiang Provincial Committee of the Communist Party of China, inspected Yucun Village, Anji County in east China's Zhejiang Province, where he learned Yucun shut down three limestone quarries and a cement factory, which accounted for 95 percent of the village's annual income. Xi praised it as a wise decision and, for the first time, put forward the important concept that "green mountains and clear waters are equal to mountains of gold and silver."

Here are some Xi's key quotes on environmental protection and green development.