中文摘要：

为了筛选对Cr（Ⅵ）净化效果好的湿地基质,通过小试实验,研究了以水稻土、红土、沙子、泥炭、硅藻土、粉煤灰为基质的李氏禾（Leersia hexandra Swartz）湿地系统对Cr（Ⅵ）的净化效果,并比较了6种基质的湿地系统中pH、Eh、有机质含量、微生物数量和李氏禾生物量的差异,结果表明,以泥炭和水稻土为基质的湿地系统的Cr（Ⅵ）净化效果显著好于其他基质的湿地系统,并且这2种基质湿地系统中李氏禾的生物量显著高于其他4种基质的湿地系统（p〈0.05）。当Cr（Ⅵ）进水质量浓度为5 mg/L时,泥炭、水稻土人工湿地对Cr（Ⅵ）的平均去除率可达到99.94%和99.54%。6种基质的pH有较大差异,但总体而言,p H较高的硅藻土和粉煤灰不利于Cr（Ⅵ）的还原去除。

英文摘要：

To screen suitable substrate of constructed wetlands （CWs） for Cr（VI） removal, six different kinds of substrate （paddy soil, peat, red loam, sand, diatomite and fly ash） were tested using a microcosm experiment. The Cr removal rate, together with pH, Eh, organic content, plant biomass and microorganism number, was analyzed. The results showed that Cr removal in the CWs using peat and paddy soil as substrate were significantly higher than those in other CWs. Moreover, the plant biomass was significantly higher in the CWs with peat and paddy soil substrates than those in the CWs with other substrates （p 〈 0.05 ）. The Cr（VI） removal rates reached 99.94 % and 99.54 % respectively in the CWs with peat and paddy soil substrates when influent Cr（VI） was 5 mg/L. The six kinds of substrate had different pH values. In general, diatomite and fly ash with high pH values were unfavorable for Cr（VI） removal.