南京市地表水重金属浓度水平探析

Analysis of the heavy metal concentration in surface water of Nanjing

为探究南京市地表水重金属浓度变化及水环境质量,文章收集南京市部分河流连续1年的重金属监测数据,进行统计、分析,研究结果显示:铜、锌、硒、砷、汞、镉、六价铬及铅的年平均浓度为2.1×10^-3,4.1×10^-3,2.0×10^-4,1.41×10^-3,8.20×10^-6,2.54×10^-5,2.03×10^-3和8.51×10^-5 mg/L,均低于国家地表水环境质量Ⅱ类标准;地表水中重金属月均值标准化后的数值总体变化幅度较低,未有明显的下降或上升趋势;锌和镉、硒和六价铬之间的相关性系数均大于0.5,且通过显著性水平为0.01的显著性检验。

In order to investigate the change of the heavy metal concentration and water environmental quality in surface water of Nanjing,the monitoring data of heavy metal in some rivers of Nanjing in one year were collected.Through statistics and analysis,the results showed that:(1)the average concentrations of copper,zinc,selenium,arsenic,mercury,cadmium,hexavalent chromium and lead were 2.1×10^-3,4.1×10^-3,2.0×10^-4,1.41×10^-3,8.20×10^-6,2.54×10^-5,2.03×10^-3 and 8.51×10^-5 mg/L,all of which were lower than the national standards of surface water environmental quality;(2)the overall change range of the monthly mean values of heavy metals in surface water after normalization were lower and don’t decrease or increase obviously;(3)the correlation coefficients between zinc and cadmium,selenium and hexavalent chromium were greater than 0.5,and they passed the significance level test of 0.01.