大气沉降重金属污染特征及生态风险研究进展

Progress in Research on Heavy Metals in Atmospheric Deposition:Pollution Characteristics and Ecological Risk Assessment

近年来,中国大气环境污染事件频发。其中大气中重金属因不能被生物降解且具有生物累积性,直接威胁人类健康而受到广泛关注。干湿沉降是去除大气中重金属的重要途径。通过收集大气干湿降尘样品,对其进行重金属含量和形态检测,分析大气中重金属污染特征和时空分布,可以解析研究区内大气沉降中重金属的来源和环境效应。研究表明,相比其他国家,中国大部分城市大气沉降重金属含量偏高。能源燃烧、交通运输、金属冶炼等生产生活活动是大气沉降重金属的主要来源。大气降尘中重金属含量随季节和区域的变化明显。该文总结概括了近年来国内外大气干湿沉降的研究成果,包括Cd、Pb、Zn、Cu、Cr、Hg和Ni等重金属的来源、污染分布特征、化学形态及其生态风险评价,并对此研究领域提出了展望。对大气污染防治规划和综合污染防治具有重要的指导意义。

With the characteristics of unbiodegradation and bioaccumulation in environment, heavy metals threaten human health, and particularly heavy metals in atmospheric deposition have been paid much attention to. This paper reviews the research progress, home and abroad, in cleaning up heavy metals in atmosphere by means of dry and wet atmospheric deposition, which involves collecting atmospheric deposition samples and detecting content and chemical form of heavy metals; analysis of atmospheric heavy metal pollution characteristics and spatial distribution in order to trace their sources and environmental effects in the study area. Researches show that compared with other countries, atmospheric deposition of heavy metals in most cities of China is high, with energy production, transportation, metal smelting being the main sources of heavy metals in atmospheric deposition. Summarily, recent achievements worldwide in researches of atmospheric dry and wet deposition and ecological risk assessment of heavy metals including Cd, Pb, Zn, Cu, Cr, Hg and Ni are reviewed, and future perspectives in this research area are put forward.