镇江市地表径流污染特征分析

摘要

[Objective] The aim was to analyze the pollution characteristics of surface runoff in Zhenjiang City. [ Method] On July 4 and Au gust 16, 2010, surface runoff in Zhengjiang City was sampled in different rainfall durations, and the variation characteristics of suspended sub stance (SS), chemical oxygen demand (CODcr) , ammonia nitrogen (NH3-N) and total phosphorus (TP) in surface runoff with rainfall dura tion were analyzed. [ Result] With the increase of rainfall duration, SS concentration in surface runoff of Zhengjiang City on July 4 and August 16, 2010 went up firstly and then went down, with the maximum concentration of 1 240 and 160 mg/L, respectively, and the decrease of SS concentration in later stage on July 4 was obviously higher than that of August 16 due to stronger rainfall on July 4. The general variation of CODcr, was similar to that of SS, and the change range of CODCr on July 4 (32 -212 mg/L) was larger than that of August 16 (13-53 mg/L). In addition, the change trends of NH3-N and TP concentration were similar, namely they increased firstly and then reduced rapidly, and the decrease of NH3-N and TP concentration was greater than that of SS at the end of rainfall. [ Conclusion] The study could provide refer ences for the study on water quality variation and treatment of rainwater runoff.%[目的]分析镇江市地表径流污染特征.[方法]分别于2010年7月4日和8月16日,采取镇江市不同降雨历时地表径流水样,分析两场降雨地表径流中悬浮物(SS)、化学需氧量(CODCr)、氨氮(NH3-N)和总磷(TP)随降雨历时的变化特征.[结果]随着降雨历时的增加,2010年7月4日和8月16日镇江市两场降雨地表径流的SS浓度先增加后减少,最大浓度分别为1240和160 mg/L,相差较大,由于7月4日降雨强度较大,降雨后期SS浓度降低幅度也较大；CODCr值的整体变化趋势与SS类似,7月4日CODCr的变化幅度(32～212mg/L)明显大于8月16日的(13～53 mg/L)；NH3-N和TP浓度的变化趋势相近,即降雨初期浓度呈增加趋势,一定时间后便急剧减少,降雨末期NH3-N和TP浓度变化比SS更为剧烈.[结论]该研究为雨水径流水质变化与处理研究提供了理论依据.