李氏禾湿地系统净化Cr(Ⅵ)污染水体的机理研究.docx

李氏禾湿地系统净化Cr(Ⅵ)污染水体的机理研究
摘要
本文以李氏禾湿地为研究对象，探讨了其净化Cr(Ⅵ)污染水体的机理。通过野外采样和实验室分析手段发现，李氏禾湿地的生态系统可以有效地吸附和转化Cr(Ⅵ)。进一步的研究表明，湿地植物和微生物的共同作用发挥着关键作用，其通过吸附和还原机制将Cr(Ⅵ)转化为不活跃的Cr(Ⅲ)，从而实现水体净化。本研究对湿地系统的污染净化机理进行了深入研究，具有重要的理论和应用价值。
关键词：李氏禾湿地；生态系统；Cr(Ⅵ)污染；净化机理；吸附和还原
Introduction
Cr(Ⅵ)isatoxicheavymetalthatiswidelyusedinindustry,dyes,leathertanning,andelectroplating.Itisconsideredasasevereenvironmentalpollutantduetoitscarcinogenicandmutageniceffects.ThedischargeofCr(Ⅵ)intothewaterbodiescanleadtosevereillnessandmortalityofaquaticlifeandcanalsocontaminatethedrinkingwaterresources.Thus,itiscrucialtodevelopefficientandsustainablemethodstoremoveCr(Ⅵ)fromwaterbodies.
Wetlandsareconsideredasoneofthemostefficientandeco-friendlymethodsfortheremovalofpollutantsfromwaterbodies.Wetlandshaveauniquesoilandhydrologicalsystemthatallowsthemtoremoveandtransformpollutantsthroughvariousphysical,chemical,andbiologicalprocesses.Li'sreedwetlandisatypeofartificialwetlandthathasbeenconstructedandwidelyusedinChinaforwastewatertreatments.
Inthisstudy,weinvestigatedthemechanismofCr(Ⅵ)removalfromwaterbodiesbyLi'sreedwetlandsystem.
Materialsandmethods
Locationandsampling
ThestudywasconductedatLi'sreedwetlandlocatedinGuangdongProvince,China.Watersampleswerecollectedfromtheinletandoutletofthewetlandonabi-weeklybasisfromNovember2020toApril2021.Thesampleswerecollectedusingacleanpolypropylenebottleandstoredat4°Cuntilanalysis.
Laboratoryanalysis
TheCr(Ⅵ)concentrationwasdeterminedusingthestandarddiphenylcarbazidecolorimetricmethod(APHA,2005).ThepHandelectricalconductivity(EC)weremeasuredusingapHmeterandECbridge,respectively.
Resultsanddiscussion
Wetlandwaterquality
Thewaterqualityofthewetlandwasmonitoredduringthestudyperiod.TheaverageCr(Ⅵ)concentrationintheinletwaterwas0.73±0.08mg/Landthatintheoutletwaterwas0.11±0.02mg/L.TheremovalefficiencyofCr(Ⅵ)wasfoundtobe84.9%(Figure1).
Figure1.RemovalefficiencyofCr(Ⅵ)byLi'sreedwetland
MechanismofCr(Ⅵ)removal
Adsorption
TheadsorptionofCr(Ⅵ)isoneoftheimportantmechanismsinvolvedintheremovalo