根据1996-2008年江苏省泗洪县境内洪泽湖7条入湖河流的水质监测数据,应用综合污染指数、灰色关联分析等方法,研究了入湖河流的水质变化规律及水质指标的空间关联特征。结果表明:(1)研究区河流按区位及水系特征可分为西部河流、东部河流、中部河流。1996-2008年间,在研究区西部较短的输水性河流水质呈现显著恶化,但中部和东部的河流水质恶化趋势不显著。(2)区内的水污染主要属有机污染,但不同区位的主要污染物不同。中部河流主要污染负荷为全氮(TN)、氨氮,西部河流主要为石油类、化学需氧量(COD),东部河流主要为石油类、TN;污染负荷存在一定的区位差异。(3)石油类、BOD5、COD、挥发酚和汞等属于相对广域性的水质指标,总体上其变化过程具有较高的区域一致性;而氨氮、TN等多为局域性水质指标。
Changes and spatial correlations of the water quality of 7 rivers of Hongze Lake were studied based on bi- monthly monitoring data from 15 sites distributed in the 7 rivers in Sihong county from 1996 to 2008. The rivers in the study area could be divided into 3 classes ; the eastern rivers were mainly for irrigation and flood drainage, the western rivers mainly acted as the channel for the upper rivers to the Hongze Lake, while the central rivers went through the ur- ban area of Sihong county. The results showed that : ( 1 ) Water quality of the western rivers was significantly deterio- rated, and that in the central and eastern rivers was slightly deteriorated. (2) The main pollutants in the study area were organic pollutants, the main pollutants in the central rivers across the urban area were TN and ammonia nitrogen ; the main pollutants of the western rivers were petroleum and COD, while petroleum and TN were the main pollutants of the eastern rivers. The pollution toad had regional differentiation. (3) BODs , COD, volatile phenols, mercury and petroleum showed similar dynamics in all three areas, while ammonia nitrogen and TN showed diverse dynamics com- paratively.