黄河兰州段水质污染监测分析

采用单因子标准指数法确定水期和断面污染类型,用综合污染指数和污染负荷比法判断水期和断面的相对污染程度。根据2005～2009年各断面24项化学指标单因子评价,研究结果表明,上游扶河桥、新城桥断面水质较好,各评价因子5年平均值均未超过地面水二类标准,属Ⅱ类水质;湟水桥、包兰桥、什川桥断面轻度污染,各评价因子5年平均值均未超过地面水三类标准,属Ⅲ类水质。断面污染负荷比依次为:包兰桥23.38%>什川桥21.85%>湟水桥21.18>新城桥18.35%>扶河桥15.18%。

Analysis of water pollution in Lanzhou section of the Yellow River

We analyzed the water phase and section pollution type by using single factor index method;besides,we studied the water phase and the relative degree of section pollution by using the methods of comprehensive pollution index and pollution load ratio. According to single factor evaluation on 24 chemical indexes in each section during 2005-2009,we found that the water quality in sections of upstream Fuhe Bridge and Xincheng Bridge was good,and the 5-year average of each evaluation factor did not exceed ClassⅡstandard for ground water,belonging to classⅡwater quality.The water in sections of Huangshui Bridge,Baolan Bridge and Shichuan Bridge was lightly polluted,and the 5-year average of each evaluation factor did not exceed ClassⅢstandard for ground water,belonging to classⅢwater quality.The poUution load ratios in sections were in the order of Baolan Bridge 23.38%>Shichuan Bridge 21.85%>Huangshui Bridge 21.18%>Xincheng Bridge 18.35%>Fuhe Bridge 15.18%.