Photos taken on Monday show wild mandarin ducks playing in Xin'an River, Huangshan city, in east China's Anhui Province.

The 359 kilometer Xin'an River originates at the Yellow Mountains in Anhui Province and extends eastwards to the west of Zhejiang Province.

In 2011, a cross-provincial ecological preservation scheme was put in place. Anhui, which lies upstream, has heavily invested in improving the water quality of the Xin'an River's upper reaches and the surrounding environment. 

Eight years on, the water quality of the Shexian County section of Xin'an River, Anhui's Huangshan city, has been improved to Grade II, the second highest level in China's five tier water quality system. This means that it can be used as a drinking water source.

(All photos via VCG. Edited by Li Yujun.)

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