中文摘要：

为明确城市大气重金属沉降对土壤环境的影响,在对南京市6个典型城市功能区连续4a大气（干、湿）沉降中重金属（Cu、Zn、Pb、Cr、Ni）含量、通量、时空变异等方面研究的基础上,结合不同功能区表土重金属含量与土壤剖面206Pb/207Pb 特征,分析其在城市土壤的累积特征。研究显示,Cu、Zn和Pb在大气沉降中强烈富集,其中又以Cu和Pb为潜在生态危害的关键元素。大气沉降导致除在相对未受城市人为活动影响的风景区外各功能区表土重金属均有明显富集,这种富集受大气沉降重金属含量和沉降量的共同影响。土壤累积模式预测钢铁工业区表土受大气重金属沉降影响的长期累积增量最大,以Zn和Pb最明显。钢铁工业区土壤剖面Pb含量和同位素特征显示表层20cm土体受大气沉降影响明显,206Pb/207Pb二元模型与预测模式对定量大气Pb沉降的土壤影响结果较一致,表明土壤中某些重金属的累积与大气沉降密切相关。

英文摘要：

Atmospheric deposition （wet and dry） of heavy metals （Cu, Zn, Pb, Cr, Ni） in six different urban function zones of Nanjing were monitored monthly from year 2005 to 2008. Heavy metals of surface soils in each zone and 206Pb/207Pb ratio in a particular soil profile were studied to explore the effect of atmospheric deposition on soil environment. Enrichment factor and potential ecological risk index showed that Cu, Zn andPb were strongly anthropogenicallyenriched, and Cu, Pb were the critical elementswith potential ecological risksin atmospheric deposition. Atmospheric deposition induced the enrichment of heavy metals in surface soils except for the forest scenic zone. Prediction results based on a simple accumulation model found that the accumulation of heavy metalsby atmospheric depositionwassignificant in the iron metallurgicalindustrial zone, especially for elements Zn and Pb. The verticaldistribution of Pb content and 206Pb/207Pb ration in thesoils in the vicinity of an iron metallurgical industrial zone showed that the influence of atmospheric deposition was mainly occurred in surface soils. The binary model of 206Pb/207Pb validated the prediction of the accumulation modelof heavy metals in iron industrial zone soil and showed that heavy metals such as Pb in the surface soils were affected obviously by atmospheric deposition.