Analysis on the Pollution Characteristics of Permanganate Index of National Surface Water in 2008—2013

The monitoring values of CODMnfrom 338 sites all over China were used to analyze the spatio-temporalchange regulation of surface water from 2008 to 2013. The temporal change,spatial change,and changes in the proportion of polluted site were analyzed. 1The pollution of CODMnbecame alleviate year by year,the average fall 32. 2% while the percentage of heavypolluted sites fall 5. 0. 2the pollution of Liaohe River,Yellow River,and Haihe River alleviated clearly and other rivers keep steadily. Haihe River was heavy polluted and Yellow River,Songhua River,Huaihe River,Liaohe River were also polluted,while the others were much better. 3 the numbers of heavy-polluted sites drop to 5 from 22,while the numbers with good water quality kept 242- 248. 4the pollution of CODMnalleviated with the COD discharge decreased,but the rivers like Haihe River were still heavy-polluted for the lack of water resource and large COD discharge.