外源沸石对铅污染菜园土修复作用研究

以油菜为供试植物,通过盆栽试验,研究了天然沸石对铅污染菜园土壤的修复作用。结果表明:施用沸石可有效降低铅的活性,抑制铅由土壤向油菜地上部的转运,降低铅在土壤中的生物有效性。随着沸石施用量的增加,土壤pH显著增加,阳离子交换量明显提高。与对照处理相比,油菜地上部和根系铅含量最高减少率可达47.4%和49.3%。研究表明天然沸石是一种有潜力的可用于修复铅污染菜园土的矿物材料,其主要是通过调节土壤pH值和CEC抑制铅的生物活性,土壤pH值为改变土壤中铅生物有效性的主导因子。

Effect of the Addition of Natural Zeolite on Remediation of Lead Polluted Garden Soil

Pb is known to be a toxic agent that accumulates in the human body over a life time. Currently, situation of pollution in vegetable production field gives some cause for anxiety. Effects of natural zeolite with different adding dose on remediation of Pb polluted garden soil were studied with pot experiment. Results showed that the application of zeolite could change soil pH and ascend CEC significantly; the soil pH increased more significantly than CEC at the same Pb treatment. Significant immobilization of Pb restraind lead uptake by rape, and the reduction of Pb concentration in shoots and roots of rape was up to 47.4% and 49.3%, respectively. The increase of soil pH was the most important factor responsible for lead immobilization, and the decreased uptake of lead by rape grown in the amended soils restrained to the bio-available fraction of lead. So, natural zeolite was a potential amendment which could remediate Pb polluted garden soil and ascend safety of edible vegetable.