Wolong National Nature Reserve is located in Sichuan Province, 
People's Republic of China. Established in 1963, the reserve is known for its Wolong Giant Panda Research Center which conduct breeding and protection research for giant pandas.
Wolong National Nature Reserve covers an area of about 7,000 square kilometres. It houses approximately 300 giant pandas, half of them in the wild; there are a total of about 1,600 giant pandas in the world as of 2007. (Giant Panda fact sheet) 
A mountain stream runs through the Wolong Valley (where the Reserve is); the stream is heavily armoured with boulders and smaller rounded stones. Stream waters are rather alkaline with pH levels in the range of 8.91. (Hogan, 2007) Water quality turbidity is quite high due to extensive sand and gravel mining in stream.