天津中心城区典型区域雨水径流污染特性

不同生活水平区域因生产结构、生活方式等因素的不同，导致雨水径流指标呈现出区域差异性特征。针对天津雨水径流污染问题，以天津中心城区降雨特征为研究对象，选取天津中心城区5个区域，研究不同生活水平区域与径流污染之间的关系。通过对试验区域内9个监测点5次降雨径流过程分析发现，天津中心城区道路径流中固体悬浮物（SS）、化学需氧量（COD）、总氮（TN）、氨氮（NH₃-N）和总磷（TP）的次降雨径流平均浓度（EMC）值分别为159.5~386.1 mg/L，74.6~157.6 mg/L，6.5~10.2 mg/L，1.9~5.4 mg/L和0.38~1.07 mg/L，屋面径流中SS、COD、TN、NH₃-N和TP的EMC值分别为107.7~135.1 mg/L，70.5~102.3 mg/L，8.3~9.1 mg/L，3.1~4.1 mg/L，0.24~0.69 mg/L；对于道路径流，SS、COD和TP浓度与生活水平拟合线的斜率分别为-104.7，-44.8和-0.28，SS、COD显著受区域生活水平影响，呈负相关关系；径流中SS与COD的相关系数为0.86，具有很强的相关性；区域生活水平越低，降雨量对径流污染的影响越大；对于屋面径流，污染浓度与区域生活水平拟合程度较差，无显著关系；降雨量对屋面径流的影响较小，主要影响因素为初期效应的强弱；区域污染源为生活源且具有高生活水平时，可采用Sartor-Boyd冲刷模型进行模拟。

Pollution Characteristics of Rain Runoffs in Typical Regions of Downtown Tianjin

There are different regional characteristics of rain runoffs due to different production structure and lifestyle in areas of different living standards. Aiming at pollution characteristics of rain runoffs in Tianjin, rainfalls collected from downtown Tianjin were taken as the research object to investigate pollution characteristics of rain runoffs in five regions of different living levels in downtown Tianjin. According to analyses on 5 rainfall processes at 9 monitoring points in test areas, it was found that the event mean concentration (EMC) of solid suspended matter (SS), chemical oxygen demand (COD), total nitrogen (TN), ammonia nitrogen (NH₃-N) and total phosphorus (TP) in the path flow of downtown Tianjin were 159.5~386.1 mg/L, 74.6~157.6 mg/L, 6.5~10.2 mg/L, 1.9~5.4 mg/L and 0.38~1.07 mg/L, respectively, and EMC values of SS, COD, TN, NH₃-N and TP in roof runoffs were 107.7~135.1 mg/L, 70.5~102.3 mg/L, 8.3~9.1 mg/L, 3.1~4.1 mg/L and 0.24~0.69 mg/L, respectively. For the path flow, the slopes of fitted lines of SS, COD and TP concentrations with the living standard were -104.7, -44.8 and -0.28, respectively, indicating that SS and COD were affected significantly by regional living levels in negative correlations. A strong correlation was found between SS and COD in runoffs with a correlation coefficient of 0.86, the lower was the living level, the greater was the impact of rainfall to the runoff pollution in the region. For the roof runoff, pollution concentrations were less correlated with regional living levels, the impact of rainfall on roof runoffs was small, while the main influencing factor was the strength of the initial effect. When the regional pollution source is the life source and the living level of the region is high, the Sartor-Boyd scouring model can be used in the simulation.