Study On The Feature Of Heavy Metal Pollution And Phytoremediation In Three Gorges Reservoir

Recent years, with the increasing of heavy metal pollution in Three Gorges Area,The plant and animal life activities are influenced seriously in the surroundings. Theorganism can accumulate heavy metal by the food chain, which endangers human health.Thus, the control of soil pollution can not be delay in Gorges Reservoir.This experiment study on Three Gorges reservoir fluctuation in YunYang, throughfield sampling and plant pot experiment to Analysis the content of heavy metals (Cu, Cd,Cr, Zn, Pb), using single-factor index and Hakanson potential ecological risk index toevaluate. Based on the results, study the absorption characteristics and tolerance of Cu,Zn, Cd by Bermudagrass, Bahiagrass and Commelina. Come to following conclusions:1.The content of Cu, Zn, Pb, Cd, Cr was respectively59.13mg/kg,115.11mg/kg,15.04mg/kg,0.46mg/kg,69.71mg/kg in study area. Using the national secondarystandard as reference, the average single-factor index of Cu was1.20, Cd was1.57.Thesoil was differently polluted by Cu and Cd. The pollution of Cd was particularlyserious.Few area was polluted by Zn and without Pb,Cr contamination.Using Hakanson potential ecological risk evaluation, the order of potential ecologicalhazard was: Cd> Cu> Cr> Zn> Pb.2.During the study period, the removal rate of Cu, Zn, Cd was respectively15.88%,10.30%,1.80%by soil degradation. The removal rate of Cu was respectively16.59%,17.47%,33.48%by Bermudagrass, Bahiagrass and Commelina. Zn was respectively25.98%,34.42%,14.68%and Cd was respectively15.97%,11.57%,2.03%.3.The time of highest removal to Cu and Cd were both10-30days byBermudagrass, prior to Bahiagrass and Commelina. Bermudagrass has the fastestadaption to Cu and Cd. So Bermudagrass can be used to restore the contamination of Cuand Cd in short-term. The time of highest removal to Zn was10-30days by Bahiagrassand Commelina, prior to. Bermudagrass. Bahiagrass and Commelina have fasteradaption to Zn. So Bahiagrass and Commelina can be used to restore the contaminationof Zn and Cd in short-term.4.In tolerance experiments, the maximum resistance to Cu of Commelina was ashigh as4562.2mg/kg; the maximum resistance to Zn of Bahiagrass was as high as5012mg/kg; and the maximum resistance to Cd of bermudagrass was as high as 960mg/kg.The experiment showed that there were a certain tolerance and removal effects ofBermudagrass, Bahiagrass and Commelina to Cu, Zn, Cd. Which can be used to restorethe heavy metal pollution in Three Gorges Reservoir fluctuation, and improve the soiland water qualityin Gorges Reservoir. Even provide practical value and reference to thelate governance of heavy metal pollution in Three Gorges Reservoir.