关键词: 非点源氮素流失, 空间分异, 多时间尺度, SWAT模型, 山美水库流域

Abstract: Based on the 2003-2009 monitoring data from seven stations in the nearshore water area of Qidong, this paper analyzed the eutrophication status of this water area and its relations to the water environmental quality of adjacent rural areas. At the stations except Pingta, there was an increasing trend in the water COD, DIN, DIP, and DO. The waters at all the stations, except at Pingtai in 2003, were in eutrophication. The nutrient status index reached the highest value in 2007, and kept dropping down after then. In the study period, the seriously polluted water area occupied 4.1% of the total, and the water quality was the worst in 2007 and 2008. The eutrophication index had a significant positive correlation with the comprehensive standard index. Relative to the discharge of urban industrial waste water and domestic sewage, the water environmental quality of adjacent rural areas as well as the runoff of Changjiang River had minor influence on the nutrient status of Qidong nearshore water area.

Key words: non-point nitrogen loss, spatial differentiation, multiple time scales, SWAT, Shanmei Reservoir watershed.