煤矸石浸出液中桐花树根的重金属富集特性的研究

Preliminary Study of Heavy Metal Accumulative Characteristics of Aegiceras Corniculatum Root in Coal Gangue Immerged Solution

以1年龄桐花树为材料,用完全营养液和不同浓度的煤矸石完全营养液浸出液进行栽培试验,对不同生长阶段的桐花树根形态指标及Cu、Zn、Mn含量进行测定和分析.结果表明:以5kg、10kg、20kg、30kg煤矸石粉分别加完全营养液配成30L培养液(分别标记为:A、B、C、D),其污染水平均超过国家I类水质的标准.其中Cu、Zn未超过II类水质标准,Mn超过II类水质标准.且煤矸石含量越高,污染也越严重.桐花树根部重金属含量的变化趋势是Mn含量较高,Zn含量次之,而Cu含量较低.且桐花树根部的Mn、Zn含量随着煤矸石浸出液浓度的增大而升高.桐花树根系在煤矸石浸出液中能够正常生长发育,表明其对煤矸石浸出液的耐性较强.试验表明桐花树对Mn、Zn是富集植物,可以考虑其作为净化污水的植物.

1 a Aegiceras Comiculatum were cultured in complete nutrient solution andcoal gangue immerged solutions to investigate the effect of coal gangue on the growth of the plant and its heavy metal accumulative characteristics. Results ： the pollution levels of all the immerged solutions with 5,10,20,30kg of coal gangue immerged in 30L complete nutrient solution have exceeded the national standard for Category I water quality; in which the Cu and Zn content were below but Mn exceeded Category II level, and pollution severity increased with the increase of amount of coal gangue immerged. The content of heavy metals in the root of Aegiceras Comiculatum increased with amount of immerged coal gangue, and demonstrated a trend that among the three metals detected Mn was the highest, followed by Zn and Cu. The normal growth of Aegiceras Corniculatum in the coal gangue immerged solution indicated that it possessed a strong tolerance to heavy metals; and the accumulation of Mn and Zn in Aegiceras Comiculatum root indicated it was a potential candidate plant for purification of polluted water.