镉污染菜田土壤原位修复效果及土壤质量变化研究

镉污染菜田土壤原位修复效果及土壤质量变化研究摘要：随着工业化和城市化的进程加快，土壤污染已成为影响人类健康和生态环境的重要问题。镉作为一种重要的重金属元素，在土壤中的污染已受到广泛的关注。本研究选择某菜田为研究对象，采用原位修复技术对镉污染的土壤进行修复，并对不同修复方案的修复效果及对土壤质量的影响进行研究。研究结果表明，通过添加大豆秸秆和棉杆的自然修复和添加壳聚糖、氢氧化铁等人工修复均可降低土壤中镉含量，但添加壳聚糖和氢氧化铁效果更为明显。土壤理化性质方面，添加大豆秸秆和棉杆的自然修复可显著提高土壤有机质含量和水分持有能力，而添加壳聚糖、氢氧化铁等人工修复则可以提高土壤pH值和交换性阳离子含量，但长期施用可能对土壤微生物群落造成不良影响。因此，在实际应用中，应结合土壤污染程度和土壤性质等因素进行修复方案的选择与优化。

关键词：镉污染；菜田土壤；原位修复；土壤质量；人工修复；自然修复

Abstract:Withtheaccelerationofindustrializationandurbanization,soilpollutionhasbecomeanimportantissuethataffectshumanhealthandecologicalenvironment.Cadmium,asanimportantheavymetalelement,hasreceivedwidespreadattentioninsoilpollution.Inthisstudy,avegetablefieldwasselectedastheresearchobject,andinsituremediationtechnologywasusedtoremediatecadmium-pollutedsoil.Theremediationeffectsofdifferentremediationschemesandtheirimpactonsoilqualitywerestudied.Theresultsshowedthatthenaturalremediationbyaddingsoybeanstrawandcottonstalksandtheartificialremediationbyaddingchitosanandironhydroxidecouldreducethecadmiumcontentinsoil,buttheeffectofaddingchitosanandironhydroxidewasmoresignificant.Intermsofsoilphysicalandchemicalproperties,naturalremediationbyaddingsoybeanstrawandcottonstalkscouldsignificantlyimprovesoilorganicmattercontentandwaterholdingcapacity,whileartificialremediationbyaddingchitosanandironhydroxidecouldimprovesoilpHandexchangeablecationcontent.However,long-termapplicationmayhaveadverseeffectsonsoilmicrobialcommunity.Therefore,inpracticalapplications,remediationschemesshouldbeselectedandoptimizedbasedonfactorssuchasthedegreeofsoilpollutionandsoilproperties.

Keywords:cadmiumpollution;vegetablefieldsoil;insituremediation;soilquality;artificialremediation;naturalremediationInsituremediationcanbeapromisingapproachtorestorethesoilqualityofvegetablefieldsaffectedbycadmiumpollution.Theuseofnaturalremediationtechniquessuchasphytoremediation,coupledwiththeapplicationoforganicamendmentslikecompost,canhelpreducecadmiumlevelsinsoileffectively,whilealsoimprovingsoilfertilityandplantgrowth.Ontheotherhand,artificialremediationmethodsusingchitosanandironhydroxidecanprovideimmediateimprovementsinsoilpHandcationexchangecapacity,buttheirlong-termeffectsonsoilmicrobiotashouldbetakenintoconsideration.

Itisimportanttonotethatthesuccessofremediationschemesdependsonseveralfactorssuchastheinitialdegreeofsoilpollution,soilproperties,andthetypeandamountofamendmentsapplied.Anintegratedapproachincorporatingdifferentremediationtechniques,alongwithpropersoilmanagementpracticeslikecroprotationandproperirrigation,canprovidelong-termsolutionstorestorethehealthandproductivityofvegetablefieldsaffectedbycadmiumpollution.

Inconclusion,theremediationofvegetablefieldsaffectedbycadmiumpollutionisacomplexissuethatrequiresaholisticapproachtotackle.Theuseofbothnaturalandartificialremediationtechniquesshouldbeconsideredbasedonsoilpropertiesanddegreeofpollution,whilealsotakingintoaccounttheirpotentialimpactsonthesoilecosystem.Througheffectiveremediationstrategies,wecanensurethesustainabilityofvegetableproduction,whilealsosafeguardingthehealthandwell-beingofconsumersTobeginwith,oneofthenaturalremediationtechniquesthatcanbeemployedtomitigatecadmiumpollutioninvegetablefieldsisphytoremediation.Thisistheuseofplantstoabsorb,accumulate,anddegradecontaminantspresentinsoil.Thereareseveralplantspeciesthathavebeenknowntoeffectivelyremovecadmiumfrompollutedsoils.Forinstance,sunflowers,Indianmustard,andalpinepennycressareknowntoaccumulatehighconcentrationsofcadmiumintheirtissues.Byplantingthesespeciesincontaminatedvegetablefields,thecadmiumlevelsinthesoilcanbereducedovertime.

Anothernaturalapproachthatcanbeusedistheuseofcomposting.Thisinvolvesthedecompositionoforganicwastesuchascropresidues,animalmanure,andfoodwasteintoanutrient-richsoilamendment.Compostenhancessoilhealth,increasingtheabilityofplantstoabsorbnutrientsfromthesoilbyreducingtheoccurrenceofheavymetalsthroughadsorptionandchelation.Compostingcanalsoreducesoilacidity,whichcanimprovetheavailabilityofnutrientssuchascalciumtotheplants.

Ontheotherhand,artificialremediationtechniquesinvolvetheuseofchemicalagentstoremoveorreducetheconcentrationofcontaminantsinsoil.Oneofthecommonlyusedtechniquesissoilwashing,whichinvolvesaddingwaterandotherchemicalagentstothesoiltosolubilizethecontaminants,afterwhichthewaterisdrainedout,andthecontaminatedwasteistakenfortreatmentordisposal.Thismethodissuitableforsoilswithlowtomoderatecadmiumpollutionlevels.

Anotherartificialremediationtechniqueistheuseofchelatingagents.Theseareorganiccompoundsthatcanbindtoheavymetals,formingcomplexesthataremoreeasilyremovedfromthesoil.Ethylenediaminetetraaceticacid(EDTA)isoneofthecommonlyusedchelatingagents,whichhasbeenshowntoeffectivelyremovecadmiumfromthesoil,althoughitsuseisassociatedwithsomedrawbacks,suchasthepotentialtocausesoilacidification.

Itisworthnotingthateachoftheabovetechniques,naturalorartificial,hasitsstrengthsandweaknesses,andtheirsuitabilitydependsontheuniquecharacteristicsofagivensite.Forexample,compostingislesssuitableforsoilsthathaveaninitialhighcadmiumcontentthatmayhindertheeffectivenessoftheprocess.Soilwashing,ontheotherhand,iseffectivebutcanleadtotheproductionofcontaminatedwastewater,whichrequiresintensivetreatmentbeforedischarge.

Inconclusion,theissueofcadmiumpollutioninvegetablefieldsisamultifacetedproblemthatrequiresanintegratedapproachtoaddress.Employingacombinationofnaturalandartificialremediationstrategies,tailoredtospecificsitecharacteristics,caneffectivelyminimizetherisktohumanhealthandtheenvironmentwhilepromotingsustainablevegetableproduction.Therefore,itisessentialtoadoptaholisticapproachtoensurethatanyremediationactivitiesundertakenminimizeanyunintendednegativeimpactsonthesoilecosystemInadditiontonaturalandartificialremediationstrategies,thereareotherapproachesthatcanbeintegratedtoaddresscontaminatedsoilinfields.Onesuchapproachisphytoremediation,whichinvolvesusingplantstoremovecontaminantsfromthesoil.Certainplantshavetheabilitytoabsorb,transformordegradecontaminantssuchasheavymetals,organicpollutants,andradioactiveelements.

Phytoremediationcanbeusedincombinationwithothernaturalandartificialremediationstrategiestoachieveoptimalresults.Forexample,amendingthesoilwithorganicmatterandfertilizerscanenhanceplantgrowthandstimulatethemicrobialactivitythatbreaksdowncontaminants.Plantingnativeplantspeciesandutilizingcroprotationandcovercroppingcanalsohelptomaintainsoilhealthandpreventfurthercontamination.Inaddition,geneticengineeringcanbeusedtoenhancetheefficacyofphytoremediationbyintroducinggenesthatimproveplantcontaminantuptakeanddegradation.

Anotherapproachthatcanbeusedinconjunctionwithnaturalandartificialremediationstrategiesissoilwashing,whichinvolvesphysicalremovalofcontaminantsfromsoil.Thistechniqueisparticularlyeffectiveforremovingcontaminantsthatarenoteasilydegradedbybiologicalorchemicalmeans.Soilwashinginvolveswashingthecontaminatedsoilwithwaterorchemicalstodissolvethecontaminants,whicharethenseparatedfromthesoilthroughvarioustechniques.Thecleansoilisthenreturnedtothefield,whilethecontaminatedwaterorchemicalsaretreatedfurtherordi