The contents of total Nitrogen ( TN) , total phosphorus ( TP ) , ammonia nitrogen ( NH+4-N) and chem-ical oxygen demand ( COD) were studied at the 90 sampling points in the 15 rivers of Yuecheng District in Sha-oxing City. The results show as follows: (1) The contents of TN, TP, COD and NH+4-N range from 0. 82 to 2. 43mg/L, 0. 19 to 0. 42mg/L, 19. 90 to 42. 80mg/L and 0. 55 to 2. 03 mg/L respectively;(2) Four pollution indexes show a synchronous trend, which meant an area with a high concentration of one pollutant has also a rel-atively high content of other pollutants. Among them, the contents of TN and TP are the highest in the eastern part of the city, closely followed by the northern part of the city. The contents NH+4-N and COD are the highest in the northern part of the city, followed by the eastern part of the city. Four indicators are the lowest in the cen-tral part of the city. On the whole, the water quality of rivers in Yuecheng District is better than the type Ⅴby the water quality standards, therefore, mainly in the typeⅣ, with inferior water quality in some stagnant waters.%在绍兴越城区15个河段的90个取样点位进行了总氮( TN )、总磷( TP )、氨氮( NH+4-N )以及化学需氧量(COD)4项指标的测定与分析.结果表明：(1)绍兴城区河水TN、TP、COD与NH+4-N含量分别处于0．82~2．43 mg/L、0．19~0．42 mg/L、19．90~42．80 mg/L与0．55~2．03 mg/L的范围；(2)4项污染指标呈现同步趋势,即某项污染物较高的区域其他污染物含量也相对较高,其中TN和TP以城东最高,城北次之,NH+4-N和COD以城北最高,城东次之,4项指标均以城中区最低.整体上,越城区主要河道水质已告别Ⅴ类水,以Ⅳ类水为主,局部沉船死水处水质较差.
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