An aerial view of the Huixian Karst National Wetland Park. [Photo by Wang Yizhao/China News Service]

Huixian Karst National Wetland Park, in Guilin's Lingui district of Guangxi Zhuang autonomous region, is the largest original Karst landform ecological wetland in the Lijiang River basin.

The Huixian wetland used to be polluted by human activity and agricultural production and during the most severe period the water quality of parts of the wetland was only V-level, the worse possible. After rounds of pollution management, the water quality all around the park has now reached III-level. 

A flock of egrets flies over the Huixian Karst National Wetland Park. [Photo by Wang Yizhao/China News Service]

The wetland has been reputed as the "kidney of Lijiang River" as it has more than 100 square kilometers of underground river system, which is of vital importance to water purification and replenishment.

Tourists tour around Huixian Karst National Wetland Park on a boat. [Photo by Wang Yizhao/China News Service]