石楠和大叶黄杨对污泥基质中重金属的吸收与富集特征

Characteristics of Absorption and Enrichmen of Heavy Metal in Photinia serrulata and Euonymus japonicus Planted in Sewage Sludge Substrates

运用不同配比的污泥基质进行盆栽试验,通过测定污泥、石楠和大叶黄杨不同部位的6种重金属含量,研究了石楠和大叶黄杨的重金属含量和富集特征。结果表明:随着栽培基质中污泥组成的变化,石楠和大叶黄杨中重金属含量与富集系数均没有呈现出有规律变化。2种植物根、茎、叶的重金属含量中均以Zn最高,根以Cd最低,茎和叶都以As最低。大叶黄杨根中6种重金属和叶片中Zn含量均显著高于石楠。在石楠中,As的含量根>茎>叶;Cd和Pb呈根显著低于茎与叶;根中Cu和Cr显著高于茎与叶;茎部Zn含量显著低于根与叶。在大叶黄杨中,As和Cu的含量均呈根>茎>叶;Cd在根、茎、叶之间无规律性,根中Cr含量高于茎与叶;茎部Pb含量高于根与叶;叶片中Zn含量低于根与茎。2种植物根、茎、叶对Cr与As富集能力均很低,而根对Cu、茎和叶对Pb富集能力很强。大叶黄杨根对6种重金属、茎对Zn与Pb的富集能力均显著高于石楠。2种植物对Cr和As的富集能力弱,而对Pb和Cd的富集能力强;大叶黄杨富集重金属能力高于石楠。

A pot experiment was conducted to investigate the characteristics of absorption and enrichmen of heavy metal in Photinia serrulata and Euonymusjaponicus planted in the various rate substrate of sewage sludge,in which the six heavy metals （As,Cd,Cr,Cu,Pb,Zn） content in roots,stems and leaves of Photinia serrulata and Euonymusjaponicus was determined. The results showed that the content and enrichment coefficient of heavy metals in Photinia serrulata and Euonymus japonicus did not regularly vary with the rate of sewage sludge in substrates. The highest content of heavy metals in roots, stems and leaves of Photinia serrulata and Euonymus j aponicus was Zn, while the lowest content of heavy metals was Cd in roots and As in stems and leaves. The content of heavy metals in roots,stems and leaves had a higher trend in Euonymus japonicus than in Photinia serrulata ,but the difference of six heavj metals in roots and Zn in leaves was significant. In Photinia serrulata ,the content of As followed the order of roots〉stems〉leaves,Cd and Pb was lower in roots than in stems and leaves,Cu and Cr was higher in roots than in stems and leaves and Zn was lower in stems than roots and leaves. In Euonymus japonicus ,the content of As and Cu followed the order of roots〉stems〉leaves,Cr was higher in roots than in sterns and leaves,Pb was higher in stems than in roots and leaves,Zn was lower in stems than in roots and leav es,and Cd had no regular distribution among roots,stems and leaves. The enriching ability of Phozinia serrulata and Euony mus japonicus to Cr and As was very weak,while it to Cu in roots and to Zn in stems and leaves was very strong. The enriching ability of Euonymus japonicus to six heavy metals in roots,to Zn and Pb in stems was significantly stronger than Photinia serrulata. In summary,2 plants had a weak enriching ability to Cr and As and a strong ability to Pb and ,Cd,and the en riching ability of Euonymusjaponicusto heavy metals was stronger than that of Pholinia serrulata.