Study On The Assessment Of Water Environment Quality In Shuimohe Valley Of Urumqi

Water quality assessment has become the basis on which water environment planning and management and integrated water control and treatment are carried out. Based on the systematic study and analysis of the assessments methods of river water quality and the water quality monitoring of Shuimo river valley in Urumqi in three years, the gray decision making-comprehensive index assessment method was developed after the deep analysis on the traditional gray decision-making assessment method and comprehensive index assessment method. This developed assessment model has been used in the water environment quality assessment in Shuimo river valley of Urumqi. Furthermore, the trend of the water quality change of the river in seven years of the major pollutants were primarily analyzed in the method of Spearman , according to this, the basic idea to treat water environment of Shuimo river valley was put forward. Through comparison between the gray decision-making assessment method and the gray decision making-comprehensive index assessment method ,it was found the latter has more advantages such as its sensitive accuracy, the assessment results reflect the dynamic change trend water environment quality more objectively ,and the gray decision making-comprehensive index model is more scientific and reasonable. Through assessment, it can be concluded that the water quality in Shuimo river valley of Urumqi was worse; the water quality did not improve in last three years, and this trend was not stable either in space or in time; the water quality was best in low water period but it's worse in flush water period and slack water period; in space the water quality in Tangcichangquan section was best , it's the second place in Qifangqiao section and Lianfengqiao section while it's worst in Miquanqiao section. According to the analysis, the trend of the water quality change of Shuimo river valley of the major pollutants, the method of Spearman was used in 1996 to 2002. It concluded, the pollutants did not have the remarkable trend of change in Tangcichangquan section,but BOD5 had very prominent raising trend in Qifangqiao section, so did BOD5, petroleum, and ammoniac nitrogen in Lianfengqiao, DO in Miquanqiao section in seven years. At last ,the primary measures on the water environmental treatment of Shuimo river valley was put forward. Severely controlling the protective area of the waterhead ; managing the disposal factory of the polluted water; increasing the treatment proportion of sewage; planning the industry category and layout with the reason; utilizing the technology of moving the water and biological technology to treat this river.