Study on comprehensive evaluation of water quality in the middle and lower reaches of Yangtze River
The Qinhuai New River and Banqiao River were selected as typical tributaries of the Nanjing section of the middle and lower reaches of the Yangtze River.Based on the online monitoring data of 11 pumping stations along the river from January to December 2023,the water environment quality and main pollution factors were evaluated by single factor evaluation method,comprehensive pollution index method,principal component analysis method and Spearman rank correlation coefficient method.The results showed that the overall water quality of Qinhuai New River was better than Banqiao River,and the main pollutants exceeding the standard were ammonia nitrogen and total nitrogen.The Class Ⅳ standard of surface water of Qinhuai New River was high.The comprehensive pollution index tended to decrease.There was good correlation among the water quality indexes.Except Wangjiashan pumping station,Block B pumping station and Guxiong Pumping station,the water quality of the other pumping stations mostly met the Class Ⅳ standard of surface water,with high comprehensive pollution index of Banqiao River Basin.The scores of principal component analysis were all greater than 6,which were mainly affected by dissolved oxygen,ammonia nitrogen and potassium permanganate index,and the correlation among each index was unsignificant.Based on the evaluation results,targeted measures can be taken for relevant water quality,thereby improving the ecological environment quality of the Yangtze River Basin.
Qinhuai New RiverBanqiao Riversingle factor evaluation methodcomprehensive pollution index methodprincipal component analysis method
NETL
NSTL
万方数据
