秸秆与粉煤灰联合施加对煤矸石污染土壤中黑麦草富集重金属的影响

EFFECT OF DOSING STRAW AND FLY ASH ON ENRICHMENT OF HEAVY METALS IN RYEGRASS IN COAL GANGUE CONTAMINATED SOIL

为探究秸秆与粉煤灰联合对煤矸石污染土壤中黑麦草富集重金属的影响,通过盆栽试验,向煤矸石污染土壤中添加粉煤灰(CS1)、秸秆(CS2)及粉煤灰与秸秆混合物(CS3),将未添加组设为对照组,分析各处理组黑麦草体内重金属元素Fe、Mn、Cu、Zn、Pb、Cd的含量,使用植物富集系数和转运系数对黑麦草富集和迁移重金属的能力进行评价。结果表明:各处理组中黑麦草对重金属的富集能力差异较大,单一修复体系中,粉煤灰有利于黑麦草地上、地下部分对Fe、Cd的富集,秸秆对促进黑麦草地上、地下部分吸收富集Fe、Mn、Pb更具潜力,粉煤灰、秸秆均抑制了黑麦草地上、下部分对Zn的吸收富集;在粉煤灰与秸秆混合处理中,黑麦草地上、地下部分对Fe、Mn的富集能力最佳。黑麦草根部对Fe、Mn、Cu、Zn、Pb、Cd的富集能力均大于黑麦草地上部分。综上,粉煤灰、秸秆及二者混合物对黑麦草地上、地下部分吸收富集Fe、Mn、Cu、Pb、Cd具有不同程度的促进作用;对Fe、Mn更具有较大的修复潜力。

To explore the effect of straw and fly ash on the accumulation of heavy metals in ryegrass in coal gangue contaminated soil,a pot experiment was conducted to add fly ash(CS1),straw(CS2),and the mixture of fly ash and straw(CS3)into the coal gangue contaminated soil,and the blank was set as the control group.The contents of heavy metal elements Fe,Mn,Cu,Zn,Pb and Cd in ryegrass in each treatment group were analyzed,and the ability of ryegrass to accumulate and migrate heavy metals was evaluated by plant enrichment coefficient and transport coefficient.The results showed that the enrichment ability of ryegrass to heavy metals in each treatment group was quite different.In the single remediation system,fly ash was conducive to the enrichment of Fe and Cd in the aboveground and lower parts of ryegrass.Straw had more potential to promote the absorption and enrichment of Fe,Mn,and Pb in the aboveground and lower parts of ryegrass.Both fly ash and straw inhibited the absorption and enrichment of Zn in the aboveground and lower parts of ryegrass.In the mixed treatment of fly ash and straw,the enrichment ability of Fe and Mn in the upper and lower parts of ryegrass was the best.The enrichment ability of ryegrass roots to Fe,Mn,Cu,Zn,Pb and Cd was greater than that of ryegrass aboveground parts.In summary,fly ash,straw,and their mixture had different degrees of promoting effect on absorption and enrichment of Fe,Mn,Cu,Pb,and Cd in the aboveground and lower parts of ryegrass.It has greater repairing potential for Fe and Mn.