Weihe Baoji section of water environmental quality synthetical analysis

Aim To understand the pollution situation and variation tendency of quality of Weihe water in Baoji.Methods Adopting the method of fuzzy comprehensive appraisal combined with weighted average, appraising the water quality of Baoji section of Weihe river from 1998 to 2002.Results Only the quality of water in 2002 is close to the standard of four grades of the national environmental quality level of surface water (GBZB1-1999), and the other years′ are higher than the standard of four grades. The variation tendency of the pollution index mainly is: chemical oxyen demand, ammonia nitrogen and high manganese sour salt index are in decline to some extent; biochemical oxygen demand is fair basically; the type of petroleum, dissolving oxygen and inferior nitrate nitrogen rise a little.Conclusion In recent years the pollution of Weihe river water is relatively serious.