The Research Of Chemical Strengthening Plant's Remediation On The Combined Pollution Of Heavy Metals-Deca-brominated Diphenyl Ether In Soils

Because of the abundant ues of the electronic equipment and the improper recycle of theelectronic waste,a large amount of heavy metals and PBDEs would be released into thesurrounding soil,which threated the security of the foods and the human health by the food chain.So,the remediation of the soil heavy metal and PBDEs contaminations would be of greatsignificance. This thesis choosed Solanum nigrum L and Lolium multiflorum L as the selectedplants, taked the heavy metals (Zn,Cd) and organic pollutant (BDE-209) as the removing objects,emplored phytoremdmiation effects on the combined pollutions under five chemicaladditives(rhamnolipids, nitrilotriacetic acid, citric acid,malic acid,β-cyclodextrin)by potexperiments,which aimed to provid theoretical foundation for the actual soil restorationapplication. The main research results were as follows:(1) The ability of bioconcentration and translocation for Zn,Cd in S.nigrum were both higherthan that in ryegrass,and the fate of puragtion for Zn,Cd by S.nigrum were alao both higher thanthat in ryegrass. The purgation fate for Zn by S.nigrum and ryegrass was between0.381%-0.606%,0.249%-0.354%individually under different chemical additives, nitrilotriaceticacid both got the best effect,which increased32.9%,42.2%individually than additives-freecontronl. The purgation fate for Cd by S.nigrum was between3.39%-5.458%under differentchemical additives, β-cyclodextrin got the best effect,which increased28.7%than additives-freecontronl. The purgation fate for Cd by ryegrass was between0.59%-0.835%under differentchemical additives,rhamnolipids got the best effect,which increased41.5%than additives-freecontronl. Nitrilotriacetic acid,rhamnolipids,citric acid,malic acid,β-cyclodextrin all increasd thepurgation fate of Zn,Cd by S.nigrum.Five chemical additives all enhanced the purgation fate ofZn,Cd by ryegrass.The purgation fate of Zn,Cd in soil by Solanum nigrum L was higher than thatby ryegrass.Nitrilotriacetic acid, rhamnolipids, β-cyclodextrin all increased the contents of availableZn,Cd in soil planted and the contents of Zn,Cd in above-ground of plants. The correlationcoefficient between contents of available Zn,Cd in soil and contents of Zn,Cd in above-ground ofplants was positive. The correlation coefficient between contents of available Zn in soil andcontents of Zn in roots was positive,but the correlation coefficient between contents of available Cd in soil and contents of Cd in roots was negative.(2) The accumulation contents of BDE-209in above-ground and root of S.nigrum was bothsmller than that in ryegrass.Five chemical additives all enhanced the contents of BDE-209inS.nigrum and ryegrass, β-cyclodextrin got the best effect.The total contents of BDE-209uptaked by S.nigrum and ryegrass was only0.549%,0.306%of reduction of BDE-209in soilindividually.The reduction fate of BDE-209in soil planted S.nigrum and ryegrass were higher thanthat unplanted, the reduction fate of BDE-209by ryegrass was higher than that by S.nigrum.Fivechemical additives all enhanced the reduction fate of BDE-209by S.nigrum and ryegrass insoil.The reduction fate of BDE-209by S.nigrum and ryegrass was between26.74%-35.41%,37.25%-45.84%individually under five chemical additives,the β-cyclodextrinsgot the best effect,which increased49.7%,32.8%than additive-free control individually.