摘要
面源是城市水体的主要污染来源之一,其负荷强度及时空分布特征对于城市水环境污染防治具有重要意义.以上海市淀北片为研究区域,选择漕河泾为代表性汇水单元,按照屋面、路面、绿地3种下垫面,于2015年期间进行大、中、小3种雨型的径流-水质同步监测,分析降雨径流特性和面源污染负荷强度,并结合GIS估算区域面源污染负荷的空间分布.结果表明:淀北片CODMn、TP、TN、NH3-N年径流污染负荷强度均值分别为385.40、4.07、57.22、11.22 kg·hm-2·a-1,总体强度较大;屋面和路面径流污染负荷均具有一定程度的初期冲刷效应,对初期55%径流采取截流措施可有效控制60%~70%的面源污染负荷;根据受纳水体河道的空间拓扑,对研究区域进行汇水单元划分,并考虑雨型对污染物EMC(事件平均浓度)的影响,可更精确地估算城市面源污染负荷及其对城市河道的影响,为城市河道水环境治理提供污染负荷来源信息,从而对河道及城市面源污染进行高效而有针对性的治理.
Non-point pollution is one of the main pollution to urban water bodies. Monitoring of the load intensity of non-point pollution and its spatio- temproal characteristics is of great significance to the prevention and governance of urban water environment. The Dianbei basin in Shanghai was selected as the study area, and the Caohejing catchment as its representative unit. The synchronous monitoring of large, medium and small types of runoff-watar quality was carried out on three diffrernt underlying surface types （ roof, road and greenland ） in the year 2015. The characteristics （ change of concentration and first flush effect） of rainfall runoff pollution and the load intensity of non-point pollution were analyzed, and the spatial distribution of non-point pollution load was further analyzed with GIS. This study found that：①The mean values of annual pollution load intensity of CODMn , TP, TN and NH3-N were 385.40, 4.07, 57.22, 11.22 kg·hm^-2·a^-1 , respectively, and in general the pollution load intensity of Dianbei basin was relatively high. ②Both the road and roof surface had a certain first-flush effect, and the initial 55% runoff interception might effectively control 60%-70% of the non- point pollution load. ③By dividing the study area into catchment units based on the spatial topology of the river and considering the effect of rainfall types on the event mean concentration of pollution, the urban non-point source pollution load and its influence on urban river channel can be estimated more accurately. This study can provide the valuable information on source of pollution and hotspot areas with high load intensity, which helps to conduct efficient and targeted management of non-point pollution for urban river water environmental governance in Dianbei basin, Shanghai.
出处
《环境科学学报》
CAS
CSCD
北大核心
2018年第2期536-545,共10页
Acta Scientiae Circumstantiae
基金
国家重点研发计划(No.2016YFC0401507)
国家自然科学基金青年基金(No.51709179)
中央级公益性科研院所青年基金(No.Y916032)~~
关键词
城市面源
上海淀北片
初期冲刷
污染负荷
汇水单元
空间分布
urban non-point pollution
Dianbei basin of Shanghai
first flush effect
pollution load
catchment unit
spatial distribution
