北京城市主干道降雨径流污染负荷分析

Analysis on pollution load of rainfall runoff in Beijing urban arterial roads

为了解城市主干道径流污染特征,于2018年6-9月对北京城市主干道降雨径流进行取样监测,运用EXCEL和SPSS软件统计分析径流污染物TSS、EC、COD、TN、TP、Zn和Ni之间的污染特性,并在此基础上估算污染物年污染负荷.研究结果表明,北京城市主干道径流水质为劣Ⅴ类;污染物浓度与降雨量、平均降雨强度、降雨历时和雨前干期长度存在一定的相关关系,依据冲刷作用与稀释作用的强弱变化,相关性有一定变化;用TSS和EC表征污染物在径流中的存在状态,发现COD、TN、Zn和Ni在径流中主要以溶解态存在,TP主要以颗粒吸附的形式存在;据实际监测数据估算,北京城市主干道年污染负荷TSS、COD、TN、TP、Zn和Ni分别为3273.15、266.86、16.24、1.89、0.097和0.008 kg·hm^-2·a^-1.城市主干道径流污染特征研究可以为城市道路径流污染防控与管理提供科学依据.

In order to characterize the urban arterial road runoff pollution, the rainfall runoff in Beijing was monitored from June to September, 2018. TSS, EC, COD, TN, TP, Zn and Ni were statistically analyzed by EXCEL and SPSS, and on this basis, the annual pollution loads were estimated. Results indicate that the arterial road water quality was inferior to the V level of the surface water criterion. There were close correlation between pollutant concentrations and precipitation, average rainfall intensity, rainfall duration and length of dry period before rain. These correlation may change owing to the flushing and the dilution. According to the correlation between runoff pollutants and TSS, together with EC, COD, TN, Zn and Ni mainly existed in dissolved state in runoff, while TP mainly existed in particle adsorption form. According to the actual monitoring data, the annual pollution loads in urban arterial roads of Beijing were calculated as 3273.15, 266.86, 16.24, 1.89, 0.097 and 0.008 kg·hm^-2·a^-1 respectively, for TSS, COD, TN, TP, Zn and Ni. The study can provide a scientific basis for the pollution prevention, control and management of urban arterial road.