关键词: 禁磷, 三峡水库, 富营养化, 绩效评估

Abstract:

〖WT5BZ〗〖WT6BZ〗() 〖JZ)〗〖WT5HZ〗Abstract: 〖WTBZ〗Previous research has shown that about 16 percent phosphorus in water body comes from the use of detergents. In order to protect the water environment of the Three Gorges Reservoir, and to prevent water eutrophication, Chongqing municipal government declared that phosphorus should never be used in detergents since 1st January, 2003. The average phosphorus content in detergents containing phosphorus is about 4 percent, and the content in detergents without phosphorus is about 0.013 percent. After being banned in detergents, the phosphorus content of detergents reduced about 99.7 percent averagely. Monitoring data revealed the reduction in total phosphorus concentration in urban wastewater. The decrease proportion in phosphorus content in central city zone is about 15.12%, in medium city about 18.36% and in county side about 33.66%. Before being banned in detergents, the phosphorus from detergents accounted for 13.77％ in total phosphorus concentration of urban wastewater, and after that the phosphorus from detergents accounted for only 0.05％. Before being banned in detergents, the phosphorus from detergents accounted for 30.53％ in total phosphorus concentration of rural wastewater, and after being banned it occupied only 0.01％. Based on the total phosphorus concentration of urban wastewater and the amount of detergents actually used by per person, about 1 056.2 t·a-1 phosphorus was cut off in urban wastewater after being banned in detergents in the urban area of Chongqing City; while 1 203.8 t·a-1 phosphorus was cut off in wastewater discharged directly to rivers in countryside.

Key words: phosphorus restriction, Three Gorges Reservoir, eutrophication, performance evaluation