通过中国知网、ISI Web of Science、万方、维普和Google scholar数据库,检索1995~2015年公开发表的关于我国大气重金属元素沉降的文献,分析研究我国大气干、湿沉降中重金属元素含量特征及时空变化,大气重金属沉降通量特征及时空变化.文献数据统计分析结果表明:近20年来我国大气降尘中Cu、Zn、Pb、Cr、Cd、As、Ni、Hg的均值或中位值含量均超过GB15618-1995《土壤环境质量标准》中的一级标准值,超标倍数分别为3.0、7.4、7.9、1.1、16.5、1.5、1.2、2.3倍;我国大气降水中Pb、Hg含量的均值或中位值超过我国地表水Ⅰ类水质标准;与1995~2005年相比,2006~2015年我国大气降尘中Pb、Cr、Cd、As、Mn、Ni均值或中位值含量降低了32%~50%;我国南方大气降尘中Cu、Zn、Pb、Cr、Cd、Ni和Hg的平均含量较北方高出60.9%、44.2%、137.5%、34.2%、68.0%、7.3%和25.0%,而As和Mn则低于北方;我国大气干湿沉降中Cu、Zn、Pb、Cr、Cd、As、Mn、Ni、Hg的年沉降通量均值或中位值分别为(10.99±14.74),(78.87±313.23), (21.81±64.53),(10.38±48.10),(0.37±1.84),(2.54±3.85),(48.00±193.40),(4.79±13.56),(0.04±0.16)mg/(m2·a);与1995~2005年相比,2006~2015年我国大气干湿沉降中Cu、Zn、Pb、Cr、Mn的沉降通量均值或中位值分别高出了11.6%、37.3%、39.1%、95.9%、117.6%, As、Ni、Hg的沉降通量均值或中位值分别降低了41.0%、21.8%、50.0%;我国北方Cu、Zn、Cr、As、Mn、Ni的沉降通量均值或中位值较南方高出42.6%、16.3%、96.8%、130.5%、307.1%、124.2%,而南方的Pb、Cd沉降通量均值或中位值高出北方22.9%、30.3%.在控制土壤重金属大气干湿沉降污染源时应优先针对Cd、Pb、Hg采取措施.%This study investigated the characteristics and spatial-temporal variation of heavy metals in atmospheric dry and wet deposition in China based on literature review. Relevant results that were published over the last two decades (i.e., from 1995 to 2015) were searched through databases including CNKI, ISI Web of Science, Wanfang, CQVIP and Google Scholar and comprehensively analyzed and compared. The average or median concentration and annual flux of heavy metals were reported in this study. Our results showed that Cu, Zn, Pb, Cr, Cd, As, Ni and Hg concentrations in atmospheric dust were higher than the Level 1standards of Environmental Quality Standard for Soils (GB15618-1995) over the last twenty years with multiple of 3.0, 7.4, 7.9, 1.1, 16.5, 1.5, 1.2 and 2.3, respectively. At the same period, Pb and Hg concentrations in rainfalls exceeded the Class I standards of Environmental Quality Standards for Surface Water (GB3838-2002). Compared to 1995~2005, Pb, Cr, Cd, As Mn and Ni concentrations in atmospheric dust decreased by 32%~50% within 2006~2015. It is noteworthy that Cu, Zn, Pb, Cr, Cd, Ni and Hg concentrations in atmospheric dust of south China were 60.9%, 44.2%, 137.5%, 34.2%, 68.0%, 7.3% and 25.0% higher than that in north China. Nevertheless, As and Mn concentrations were lower in south China .The annual fluxes of Cu, Zn, Pb, Cr, Cd, As, Mn, Ni and Hg in atmospheric dry and wet deposition were (10.99±14.74), (78.87±313.23), (21.81±64.53), (10.38±48.10), (0.37±1.84), (2.54±3.85), (48.00±193.40), (4.79±13.56) and (0.04±0.16)mg/(m 2 ·a), respectively; The annual fluxes of Cu, Zn, Pb,Cr and Mn in atmospheric dry and wet deposition between 2006 and 2015 were increased by 11.6%, 37.3%, 39.1%, 95.9% and 117.6% when comparing with these between 1995 and 2005; While As, Ni and Hg were reduced by 41.0%, 21.8% and 50.0%, respectively; When comparing different regions of China, the annual fluxes of Cu, Zn, Cr, As, Mn and Ni in atmospheric dry and wet deposition in north were 42.6%, 16.3%, 96.8%, 130.5%, 307.1% and 124.2% higher than these in south respectively. By contrast, Pb and Cd annual fluxes in south were 22.9% and 30.3% higher than these in north. Thus, Cd, Pb and Hg have high priority in preventing heavy metals in soil from atmospheric dry and wet deposition.
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