环境材料对Pb、Cd污染土壤玉米生长及土壤改良效果的影响

摘要

为探索环境材料对种植于Pb、Cd污染土壤中的玉米生长、品质的影响,以及对Pb、Cd重金属污染土壤的改良效应,本文采用温室盆栽方法,研究了不同环境材料[腐殖质类材料(HA)、高分子材料(SAP)、煤基复合材料(FM)及粉质矿物材料(FS)]及其复合处理对Pb-Cd复合污染土壤中玉米(Zea mays L.)生长、品质及根系土壤环境的影响.结果表明,添加环境材料组合F22(FM+SAP)、F23(FS+SAP)及F32(HA+SAP+FS)能促进苗期玉米生长,长势好于对照；所有环境材料处理中玉米地上部粗灰分含量都低于对照,添加单一环境材料对玉米地上部粗淀粉含量的提高效果高于对照、优于组合；处理FM、F33(SAP+FM+FS)及F4(HA+SAP+FM+FS)对土壤中Pb固定效果显著,抑制土壤中Pb向玉米体内迁移；单一处理FM、FS及组合F33(SAP+FM+FS)对土壤重金属Cd固化效果明显,抑制土壤中Cd向玉米体内迁移.环境材料的添加在一定程度上有助于土壤基本理化性质的改善,促进土壤改良,同时环境材料对阻止土壤重金属向植物体迁移有一定作用.%Application of environmental materials is a vital remedial measure of heavy metal lead (Pb) and cadmium (Cd)) contaminated soils. To explore the effects of environmental materials on plant growth and quality and to enhance remediation of Pb and Cd contaminated soils, a pot experiment was setup in greenhouse conditions. The experiment analyzed soil properties, growth and quality as well as Pb and Cd contents of maize (Zea mays L.) in Pb-Cd contaminated soils. Different environmental treatments, including single environmental materials treatments [e.g., humus (HA), polymers (SAP), coal-derived composites (FM) and powder minerals (FS)], and composite treatments of environmental materials were selected in heavy metal Pb and Cd contaminated soils. The results indicated that F22 (FM+SAP), F23 (FS+SAP) and F32 (HA+SAP+FS) composite treatments promoted stronger maize growth at seedling stage than that of the control. Maize crude ash in all the treatments with environmental materials was less than that of the control. Also maize crude starch in single environmental material treatments was higher than that in composite environmental material and control treatments. By comparison, single FM and combined F33 (SAP+FM+FS) and F4 (HA+SAP+FM+FS) treatments hada significant inhibition effect on maize Pb uptake in Pb-Cd contaminated soils. Similarly, single FM and FS and composite F33 (SAP+FM+FS) environmental materials treatments had a significant prohibition effect on maize Cd uptake in Pb-Cd contaminated soils. Thus the application of environmental materials could improve soil physical and chemical properties and inhibited crop heavy metal uptake.