Water quality of surface water and its variation trend in Yangtze River Source Area of Qinghai from 2005 to 2012

The surface water quality and the variation trend around the Yangtze River Source Area were analyzed based on the monitoring data of surface water from 7 main monitoring cross-sections for successive 8 years from 2005 to 2012. The result shows that the water quality ratio in each monitoring section between Ⅰ and Ⅲ is 100%,which means that the overall condition of surface water in this area is optimal and the water quality grade is Class I.The main pollutants in surface water contain Permanganate,Ammonia nitrogen and 3 kinds of Total Phosphorus.However these element concentration in the surface water is at the state of background value,which hardly has impact on human body.