Abstract:

 Based on the 2010 census data of the industrial pollution sources of Danjiangkou Reservoir area and upper reaches, analyses on total discharge amount of COD and NH3N in wastewaters were carried out at different levels of administrative division Discharge amounts and industrial source proportions of total COD and NH3N discharged from industrial pollution sources were selected to analyze the pollution characteristics and industrial contribution to the water pollution Spatial distribution characteristics and pollutant characteristics of the industrial pollution sources were also analyzed using Chinese standard industrial classification as a reference The results showed that the total discharge amount of COD and NH3Nin wastewaters from the industrial pollution sources of Danjiangkou Reservoir area and upper reaches were 17 9197 t and 2 8413 t Among them, Shaanxi Province accounted for 583% COD and 806% NH3N discharged from industrial pollution sources of the entire area, ranking the first place of the largest proportions of pollution discharged in all three provinces of this areaThe results also indicated that most pollution sources around Shiyan City threatened Danjiangkou Reservoir and water pollution emergency was ready to happen at any time Hanzhong City and Shangluo City ranked second and third in the contribution proportions of total wastewater discharge for both COD and NH3N, with 226% and 194% for COD, 359% and 381% for NH3N, respectively In terms of industrial pollution contribution, food, petrochemistry and harmacy industries were the top 3 industries that contributed 40%, 19% and 16% for COD discharged industrial pollution sources of Danjiangkou Reservoir area and upper reaches, while petrochemistry, mining and metallurgy industries were the main industies for NH3N discharged and their proportions were 45%, 20% and 17%, respectively The largest value of industrial wastewater discharged per ten thousand yuan industrial output were from leatherindustry which was 335kg COD per ten thousand yuanindustrial output Papermaking industry had 251kg COD per ten thousand yuan industrial output, which was ahead of the other industries As for NH3N, leather was the industry with the highest NH3N discharge and lowest economic output, with 470  kg NH3N per ten thousand yuan industrial output valueBy analyzing spatial distribution characteristics of industrial pollution sources, it was found that Shiyan City, Hanzhong City, Shangluo City and Ankang City had the most significant influence on water pollution in Danjiangkou Reservoir area and upper reaches From the view of Chinese standard industrial classification, it was told that the traditional industry, such as paper making and lether, usually both had higher NH3N or COD discharges and lower economic outputs, should be put in the predominant position when adjusting industial insutcture and developing the socialeconomy of Danjiangkou Reservoir area and upper reaches It also was concluded that more attention should be paid to water pollution control of the whole area by the viewpoint of “integrated basin”and all localities and departments should take efficient and effective measures, such as division management of key industriesand pollution area, taking implement step by step and carrying out longterm supervision to ensure water quality of Danjiangkou Reservoir