根据浙江省11个地级市城市灰尘数据,分析灰尘重金属Pb,Cu,Zn,Ni,Cr,Co在省域尺度上的分布规律。结果显示,浙江省灰尘重金属含量整体表现为西北低、东南高,西南低、东北高,由内地向沿海市区升高。各地市均表现出明显不同的变化特征和累积量,舟山市具有较强的灰尘重金属累积和较低的空间变异;杭州市灰尘重金属的累积和变异程度都较高;温州、嘉兴、宁波等沿海市区灰尘重金属富集明显,但空间变异性低;金华市灰尘重金属变异程度相当,但Pb,Zn,Cu累积明显;台州、绍兴的Ni,Cr累积量低,但变异程度高;衢州Cu,Zn的累积和Cr,Co的变异高;湖州、丽水灰尘重金属的累积和变异程度都较低。灰尘重金属在省域上累积程度是Cu〉Zn〉Pb〉Cr〉Co〉Ni,变异较强的是Pb、Zn、Cu,较弱的是Co、Cr,而Ni的累积程度和空间变异都较低。研究发现人类活动是浙江省灰尘重金属输入的绝对重要影响因素,地形特征、地表径流和盛行风对城市灰尘重金属的迁移、扩散和稀释也具有重要作用。
According to the dust date coming from 11 cities in Zhejiang,Pb,Cu,Zn,Ni,Cr,Co distribution and characteristic on provincial scale were analyzed.The results showed that: For heavy metal content,the southeast and northeast were high,northwest and southwest were low,meanwhile the content increased from the mainland to the coastal cities gradually.Cities reflected different variations and accumulation.Zhoushan had a high heavy metal accumulation and low spatial variability.The accumulation and spatial variability of heavy metals in Hangzhou were high.Coastal cities for Wenzhou,Jiaxing and Ningbo expressed strong accumulation and weak variability.Jinhua was in the position of moderate variation,but Pb,Zn,Cu accumulation were significantly.Ni,Cr in Taizhou and Shaoxing showed a low accumulation and a high spatial variability.Quzhou had high accumulation of Cu and Zn,while a strong spatial variability of Cr and Co.The accumulation and spatial variability for heavy metals in Huzhou and Lishui were low.The accumulation of heavy metal in urban dust on provincial scale was the order of Cu Zn Pb Cr Co Ni,at the same time,Pb,Zn and Cu showed a strong variation,Co and Cr demonstrated the weak,while Ni was weak in the accumulation and the variation.Human activities is the important factor of heavy metal input.In addition,terrain,surface runoff and monsoon also have strong influence on the migrate,spread and dilution for heavy metal in urban dust.