洛阳市大气PM2.5中重金属元素特征来源及潜在生态风险评价

Heavy metal characteristic sources and ecological risk assessment of atmospheric PM2.5 in Luoyang City

研究大气PM2.5中典型重金属元素的特征来源及其潜在生态风险对区域大气环境保护十分重要。以洛阳市2015年大气PM2.5为研究对象,采用富集因子法研究了PM2.5中9种重金属元素受人为源的影响程度;结合区域产业结构特点和能源消费情况,辨析了重金属元素的主要来源;基于潜在生态风险指数法评价了重金属的潜在生态风险程度。结果表明:洛阳市大气PM2.5中重金属浓度水平具有明显的结构性排放和人为源特征,其中Cd元素富集水平最高,与煤炭燃烧、涂料建材生产排放源紧密相关;Zn、Pb和As次之,主要来源为垃圾焚烧、机动车尾气和有色冶金;Cu的人为影响也不可忽视,主要来源为机动车尾气和金属冶炼废气排放;重金属生态风险总体评价为“中等”级别,Cd是最主要贡献者,可通过控制涂料建材和有色冶金等企业污染物排放、加强燃煤管理来降低其生态风险。本研究对洛阳市实施大气精准治理和持续提升大气环境质量具有指导意义。

It is very important to analyze the characteristic sources and potential ecological risks of typical heavy metals in atmospheric PM 2.5 for regional atmospheric environmental protection.The influence degree of 9 heavy metal elements in PM 2.5 of 2015 in Luoyang City by human sources was studied using enrichment factor method;combined with the characteristics of regional industrial structure and energy consumption,the main sources of heavy metal elements were identified.And the potential ecological hazard degree of heavy metals was evaluated based on the potential ecological risk index method.The results indicated that the concentration of heavy metals in PM 2.5 in Luoyang City has obvious structural emission and anthropogenic source characteristics.The enrichment level of Cd was the highest,which was closely related to the emission sources of coal combustion,coating and building materials production.The second was Zn,Pb and As,they mainly came from waste incineration,vehicle exhaust and non-ferrous metallurgy.The influence of Cu should also be paid attention,which came from vehicle exhaust and metal smelting exhaust gas.The overall ecological risklevel of heavy metals was"medium",and Cd was the most important contributor.The ecological risk can be reduced by controlling pollutant emission from coating production,non-ferrous metallurgy enterprises,and strengthening the management of coal combustion.This study has guiding significance for the implementation of precise governance and continuous improvement of atmospheric environmental quality in Luoyang City.