植物对河道污染沉积物中重金属的修复

Phytoremediation of Heavy Metal in Dredged Sewage River Sediment

针对河道沉积物中的重金属污染问题,采用温室栽培试验研究了黑麦草对河道污染沉积物中重金属Ni,Cu和Cd的修复效果.结果表明:3种重金属在黑麦草地上部分的累积量均小于地下部分,其中Ni地上部分为63.014 mg.kg-1,为沉积物中Ni总量的1/3;Cu地上部分为92.356 mg.kg-1,约占Cu总量的1/5;Cd地上部分为1.449 mg.kg-1,占Cd总量的1/4.地上部分累积的重金属量与离子交换态量有相关性.沉积物中的微生物种类和数量在种植前后有较大变化,种后沉积物中多酚氧化酶和过氧化氢酶活性均有所增加.

Pot experiment was conducted to study phytoremediation of Lolium multiflorum Lam to heavy metal （Ni,Cu,Cd） contaminated dredged sewage river sediment. Results show that the plant has high accumulation ability to the heavy metal in dredged sewage river sediment and the shoot of the plant accumulated more amounts of Ni, Cu, and Cd than the root. The most amount of heavy metal-Ni and Cu in the shoot of Lolium multiflorum Lam is 63. 014 mg · kg-1 and 92. 356 mg · kg -1 respectively,the same to 1/3 and 1/5 of the whole amount. The amount of Cd in the shoot is 1. 449 mg · kg -1, the same to 1/4 of the root. The accumulated amounts of heavy metals in the shoot have more direct relation with ion exchangeable heavy metal amount. It has been proven that the plant promoted the growth of the root microorganism and activities of rhizosphere. The activities of polyphenol oxidize and catalase increased after planting.