风干污泥修复后淋洗液对黑麦草初期生长与重金属富集的影响  

Effects of Air Dried Sewage Sludge Leachate After Remediation on Initial Growth and Heavy Metal Accumulation of Lolium perenne

作　　者：沈志平[1] 多立安[1] 赵树兰[1] 

机构地区：[1]天津师范大学生命科学学院,天津市动植物抗性重点实验室,天津300387

出　　处：《农业环境科学学报》2013年第5期937-943,共7页Journal of Agro-Environment Science

基　　金：天津市科技支撑计划重点项目(09ZCGYSH02100)

摘　　要：采用不同浓度DTPA强化修复风干污泥中的重金属,之后对基质进行淋洗,以获得的淋洗液培植黑麦草,研究了淋洗液对黑麦草初期生长及重金属富集的影响。结果表明,淋洗液中含有丰富的无机矿质元素,能够满足植物的生长需要。与对照相比,修复过程中20 mmol.kg-1DTPA未种植物处理的淋洗液显著抑制黑麦草的萌发,推迟黑麦草萌发的高峰期,且降低了黑麦草的地上生物量,其余处理的萌发数与对照差异不显著。各处理淋洗液培养的黑麦草在叶绿素含量上较对照有不同程度的增加,其中10 mmol.kg-1DTPA+隔层处理的淋洗液较对照提高了91.2%。在对重金属的富集中,各处理淋洗液培植的黑麦草地上部和根部的Cd、Cr、Cu、Zn和Pb的浓度显著提高,尤其20 mmol.kg-1DTPA未种植物处理要显著高于对照和其他淋洗液处理。对于同一金属而言,同一处理下根部浓度要远远高于地上部。相同处理下,黑麦草地上部对不同重金属富集系数表现为Zn最大,Pb最小,根部则表现为Cd、Pb较大,Zn较小,且Zn从地下向地上的转运能力最强。和其他4种重金属相比,黑麦草对Zn具有较强的吸收潜力,可作为Zn污染土壤植物修复的备选植物。In our previous study,a column experiment with horizontal permeable barriers was conducted to investigate DTPA-assisted phytoextraction of heavy metals by turfgrass from air dried sludge and associated heavy metal leaching.Thus,large amounts of leachates contained excessive heavy metals were obtained.In order to avoid the leachate pollute the environment and to utilize it,Lolium perenne was cultivated by the leachates and the effects of the leachates on initial growth and heavy metal accumulation were investigated.The results showed that the leachates were rich in inorganic mineral nutrients for plant growth.Compared to the control,the leachate obtained from the treatment of 20 mmol·kg-1 DTPA in the absence of turfgrass planting significantly inhibited seed germination,delayed germination peak and decreased aboveground biomass.But there was no significant differences between other treatments and control.All leachate treatments significantly increased chlorophyll content,which is increased by 91.2% in the leachate from the treatment of 10 mmol·kg-1 DTPA in the presence of barrier.For heavy metal accumulation,the leachates significantly increased Cd,Cr,Cu,Zn and Pb concentrations in turfgrass shoots and roots,especially the treatment of 20 mmol·kg-1 DTPA in the absence of turfgrass planting.With respect to the same metal,metal concentration in root was higher than that in shoot under the same treatment.The bioconcentration factor(BCF) of heavy metals for shoots showed the biggest for Zn and smallest for Pb.However,BCF for roots showed higher for Cd,Pb and lower for Zn.Also,zinc showed strong transfer ability from root to shoot among the five metals.It was considered that relative to the other four heavy metals,Lolium perenne could be selected as a potential candidate for the phytoextraction of soil contaminated with Zn.

关 键 词：风干污泥 淋洗液 黑麦草 初期生长 重金属富集 

分 类 号：X503.233[环境科学与工程—环境工程]