沙颍河重要闸控断面水质变化及影响因素分析

Analysis of Water Quality Change and Influencing Factors in Important Gate Sections of Shaying River

研究采用箱线图法和单因子水质指标评价法分析2009～2013年沙颍河重要闸控断面氨氮和高锰酸盐指数的年际年内变化规律,并探讨水质变化的主要影响因素。结果表明,近年来氨氮和高锰酸盐指数污染有所减轻;氨氮年内变化大,污染较重,非汛期浓度显著高于汛期;高锰酸盐指数年内较稳定,汛期浓度略低于非汛期,污染较轻;沿线的氨氮和高锰酸盐指数浓度呈降低的趋势;工农业废水的排放、化肥农药的施用和闸坝运行状况是影响沙颍河水质变化的主要因素。

The box-line method and single-factor water quality evaluation method are adopted to analyze the change law of ammonia nitrogen and permanganate index in Shaying River between 2009-2013, and the main influencing factors of water quality change are also discussed. The results show that （a） the pollution of ammonia nitrogen and permanganate index have slightly reduced in recent years; （b） the ammonia nitrogen changes greatly during a year with the concentration in non-flood season being significantly higher than that in flood season, and the pollution is heavier; （c） the permanganate index is more stable during a year with the concentration in flood season being slightly lower than that in non-flood season, and the pollution is lighter; （d） the concentration of ammonia and permanganate index along the route shows a decreasing trend; and （e） the discharge of industrial and agricultural wastewater, the utilization of chemical fertilizers and pesticides and the operation conditions of gate dam are the main factors affecting water quality of Shaying River.