吊兰对土壤Cd、Pb形态与土壤酶活性的影响

为探讨观赏植物吊兰(Chlorophytum comosum)对Cd、Pb污染土壤的修复效果,通过盆栽试验,研究了吊兰对Cd、Pb胁迫下土壤酶活性和重金属形态分布的影响。结果表明,过氧化氢酶、蔗糖酶、脲酶以及磷酸酶活性均表现为实验组空白组,且实验组随着吊兰培养时间的增加,4种酶活性呈先增加后减小趋势。吊兰栽培120d时,Cd处理组和Pb处理组4种土壤酶的最大活性分别达到:1.936U/g、263.170U/g、36.881U/g、57.992U/100g和3.544U/g、302.000U/g、155.502U/g、65.451U/100g。空白组与实验组变化趋势相似。和空白组相比,重金属Cd、Pb残渣态在实验组中显著下降;Cd碳酸盐结合态在实验组中显著增大。通过双变量相关性分析发现,土壤重金属残渣态与可交换态含量的变化量,对土壤酶活性的影响较大,其他形态的变化虽然也有影响,但没有统计学意义(P0.05)。研究结果表明,吊兰生长能够有效改善土壤环境,降低土壤Pb、Cd污染程度,有利于Pb、Cd污染土壤的修复,在重金属Cd、Pb污染修复方面有广阔的应用前景。

Effects of Chlorophytum comosum on Cd and Pb speciation and soil enzyme activities

Pot experiments were conducted to evaluate the effects of planting Chlorophytum comosum on enzyme activities and heavy metal forms in the soil under Cd and Pb stress.Results showed that the activities of catalase,sucrose,urease and phosphatase increased gradually and reached their maxima at 1.936 U/g,263.170 U/g,36.881 U/g,57.992 U/100g,respectively,under Cd stress and 3.544 U/g,302.000 U/g,155.502 U/g,65.451 U/100g,respectively,under Pb stress on the 120^th day of planting.The variation trend of soil enzyme activity of the blank control group was similar to that of the experimental groups.Based on bivariate correlation analysis,it was found that the changes of heavy metal residue and exchangeable state had great influence on soil enzyme activities.While other forms of changes had no statistical significance impact.Since the growth of C.comosum could reduce the pollution of Pb and Cd in soil,improve the soil environment effectively,it was beneficial to the remediation of Pb and Cd contaminated soil,and it had wide application prospects in the repairation of Cd and Pb pollution.