太湖西岸水质变化趋势及主要驱动因子

Trend and dominating factors of water quality change in the west bank of Taihu Lake

基于2009—2015年太湖西岸10个监测断面的8个水质指标数据,采用季节性Kendall检验法对其指标的浓度变化趋势进行分析,并用主成分分析法结合相关分析评价历年水质状况,分析影响太湖西岸水质的主要驱动因子。结果表明:(1)2009—2015年太湖西岸COD下降趋势显著,DO非显著上升,电导率、高锰酸盐指数、BOD5、氨氮、TP和TN均表现为高度显著下降趋势。(2)主成分分析从原始信息中提取出两个主成分,共解释了73.645%的结果,分别代表水质氮磷营养盐和有机污染。综合得分表明,2009—2015年太湖西岸水质呈逐年改善趋势。水质污染在空间上表现为北部向南部递减的趋势。(3)相关分析表明,氨氮和COD是影响该区域水质的主要驱动因子。

Based on 8 parameters monitored at 10 control sections of the west bank of Taihu Lake during 2009- 2015, seasonal Kendall test was used to analyze the changing trend of index concentration. Combined with related ana- lyses of water quality in calendar year, principal component analysis was used to analyses the dominating factors influ- encing the water quality in the west bank of Taihu Lake. The results showed that： （1） COD was significantly de- creased. DO was non-significantly risen. Electrical conductivity, permanganate index, BODs, ammonia nitrogen, TP and TN were highly significantly decreased in the west bank of Taihu Lake during 2009-2015. （2） 2 principal compo- nents were extracted from the original monitoring data by principal component analysis,which explained 73.645% of the results and represented of nitrogen and phosphorus nutrient salt and organic pollution of water quality. Compre- hensive score showed that water pollution improved year by year in the west bank of Taihu Lake during 2009-2015. The water pollution was showed a downtrend from the north to the south in space. （3） Correlation analysis showed that ammonia nitrogen and COD were the dominating factors influencing the water quality in this area.