关键词: 水质, 单因子评价方法, GIS空间分析方法, 里下河腹部区

Abstract: Based on the monthly water quality data of 86 monitoring sections of 46 rivers in Lixiahe abdominal area from 2010 to 2018, this paper analyzes the spatial and temporal variation characteristics of water quality by using single factor evaluation method and GIS spatial analysis method. Analysis on temporal variation of water quality shows that the water quality in the flood season(May～September) is worse than that in the non-flood season(January～April, October～December). The worst water quality period is in July, while the best one is in December. In recent years, the permanganate index and ammonia nitrogen concentration have shown an obvious downward trend. Spatial variation analysis of water quality shows that the water quality in non-flood season is generally good, but it is poor in Xinghua City and Gaoyou City sections in the central part. Water quality in flood season is generally poor, only some of the main watershed or regional river channels meet water quality standards, and water quality in the southwest, northeast and central areas are the worst. The temporal and spatial variation of regional water quality is closely related to the volume of externally introduced water. Effects of external introduced water on improving regional water quality are increasing.

Key words: water quality, single factor evaluation method, GIS spatial analysis method, Lixiahe abdominal area;