简介：Effectsofnon-ionicpolyacrylamide(PAM),anionicpolyacrylamide(PHP),cationicpolyacrylamide(PCAM),non-ionicpolyvinylalcohol(PVA),anionichydrolyzedpolyacrylonitrile(HPAN)andpolyethleneoxide(PEO)onthephysicalpropertiesofthreedifferentsoilstpeswerestudied.contentofwater-stableaggregateslargerthan0.25mmincreasedtovaryingextentsfordifferentsoilsandsoilconditioners,Amongthesixkindsofcondiftioners,non-ionicpolyacrylamide(PAM)wasthemosteffectiveforredsoilwhilepolyethyleneoxide(PEO)theleasteffectiveforChaosoil,redsoilandyellow-brownsoil.Water-stableaggregateswiththemolecularweightofPEOwithinacertainrange.OnlyevaporationrateofChaosoildecreasedafteraplicationofPAMandHPANtoChaosoilandredsoil.

简介：CorrelationandpathanalysismethodswereusedtostudytherelationshipbetweensoilpropertiesandthedistributionofdifferentsoilHgfractionswithninerepresentativesoilsfromChongqing,China.Resultsshowedthatclay(＜2m)couldincreasewater-solubleHg(r=0.700*).Soilorganicmatter(OM)couldenhancetheincreaseofelementalHg(r=0.674*).Thehigherthebasesaturationpercentage(BSP),themoretheresidualHg(r=0.684*).OrganicHg,thesumofacid-solubleorganicHg.andalkali-solubleHg,waspositivelyaffectedbysilt(2～20μm)butnegativelyaffectedbypH,withthedirectpathcoefficientsamountingto1.0487and0.5121,respectively.ThepositiveeffectofOMandnegativeeffectofBSPonorganicHgwerethemostsignificant,withthedirectpathcoefficientsbeing0.7614and-0.8527,respectively.Theindirecteffectofclay(＜2μm)viaBSP(pathcoefficient=0.4186)wasthehighest,showingthattherealinfluencingfactorintheeffectofclay(＜2μm)onacid-solubleorganicHgwasBSP.SincetheavailableHgfraction,water-solubleHg,waspositivelyaffectedbysoilclaycontent,andthequiteimmobileandnotbioavailableresidualHgbysoilBSP,suitablereductionofclaycontentandincreaseofBSPwouldbeofmuchhelptoreducetheHgavailabilityandHgactivityinHg-contaminatedsoils.

简介：Thisstudywasdesignedtounderstandtheimpactofmethylbromide(MB)(CH3Br)anditsalternativesonbothfree-livingandroot-knotnematodesinthesoil.Arandomizedcompleteblockexperimentwithsixtreatmentsand4replicates(eachreplicateinaseparategreenhouse)wasestablishedinQingzhou,ShandongProvince,China.InadditiontoMBanduntreatedcontrol(CK)treatmentstherewerefouralternativesoilfumigationpracticesincludingMB+virtuallyimpermeablefilms(VIF),metamsodium(MS),MS+VIFandsoilsolarizationcombinedwithselectedbiologicalcontrolagents(SS+BCA).Twotomato(LycopersicumesculentumMill.)cultivars,cv.Maofen-802fromtheXianInstituteofVegetableScience,China,andcv.AF179BrillantefromtheIsraeliHazeraQualitySeeds,wereselectedastestcrops.TheresultsindicatedthatRhabditidaewasthemostdominantpopulationwithpercentageabundanceashighas85%ofthetotalnumberofidentifiedfree-livingnematodes,followedbythatofCephalobidae.Methylbromideanditsalternativesexceptforthenon-chemicalSS+BCAtreatmentcontrolledthetargetpest,root-knotnematodes.Also,theimpactofthethreechemicalalternativesonfree-livingnematodenumberandfunctionalgroupabundancewassimilartotheimpactassociatedwithatypicalmethylbromideapplication.Chemicalfumigationpractices,especiallythatwithMB,significantlyreducedthenumberofnematodesinthesoilandsimultaneouslysignificantlyreducedthenumberofnematodegeneratherebyreducingnematodediversity.Allthefoursoilchemicalfumigationactivitiesdecreasedsoilmicrobialbiomassandhadanobviousinitialimpactonmicroorganismbiomass.Furthermore,bothplant-parasiticandfungivorenematodeswerepositivelycorrelatedwithsoilmicrobialbiomass.

简介：Soilcrustingmayhavesignificantimpactsoninfiltration,runoffgenerationanderosioninagriculturallandsorsemi-aridandaridsoils.Thepreviousinvestigationsonsoilcrustingwereoftenconductedundersimulatedrainfallconditions.Thisstudyaimstoevaluatetheeffectsofsoilcrustingonsoilmoistureduringinter-stormperiodsandsoilandwaterlossesduringstormperiodsundernaturalrainfalls.ThestudysitewaslocatedintheLoessPlateauofChina.Fourplotswithauniformslopeandsizewereselected.Soilcrustswerekeptintactonthetwoplotsthroughoutthemonitoringperiodsof1999and2000,butwerebrokenaftereachrainstormeventontheothertwoplots.Soilmoisturewasmeasuredonallplotswithanintervalofoneweekatthreedepthsandtotaleventrunoffandsedimentdischargesweremeasuredineachstorm.Itwasfoundthatnomarkeddifferenceinsoilmoistureandrunoffexistsbetweenthecrustedanduncrustedplots.Thisisbecausetherapiddevelopmentofnewcrustsontheuncrustedplotsduringthestormevents.However,theerosionrateontheuncrustedplotswassignificantlyhigherthanthatonthecrustedplots,whichwasmainlycausedbythedisturbanceofthesurfacesoilsontheuncrustedplots.ThisstudyquestionstheeffectivenessofacommonagriculturalpracticeintheLoessPlateau,hoeinglandsafterrainfall,inreducingrunoffanderosion.

简介：Successionrulesofsoilacidityqualityoflarchplantationsinfirstrotationatdifferentdevelopmentstages,successionrulesofsoilacidityqualityofyoungstandoflarchplantationsinsecondrotationandtherelationshipbetweensoilacidityandvariousformsoforganicphosphorusandinorganicphosphoruswerestudiedinmountainousareaofeasternpartofNortheasternChina.Theresultsshowedthatactiveacidity(pHvalue)inrhizospheresoildecreasedcontinuallywithstandageincreasingfromyoungstand,half-maturestand,nearmaturestandtomaturestand,butactiveacidity(pHvalue)innon-rhizospheresoil,exchangeacidity,exchangeablealuminium,totalhydrolyticacidity,andtheratioofexchangeacidityandtotalhydrolyticacidityinrhizospheresoilandinnon-rhizospheresoilincreasedapparently;totalorganicP,moderatelyresistantorganicP,andhighlyresistantorganicPinsoildecreasedatallagestagesinlarchplantationswhensoilacidityadded.Forrhizospheresoilofallstandsoflarchplantationsatdifferentdevelopmentstages,therewaspositivecorrelationbetweenCa-P(exceptinyoungstand),Al-P(exceptinhalf-maturestand),Fe-P(exceptinnearmaturestandandmaturestand),O-P(exceptinyoungstand),andsoilactiveacidity,respectively;Forrhizospheresoil,therewasnegativecorrelationbetweenCa-P(exceptinhalf-maturestand),Al-P(exceptinyoungstand),O-P,andexchangeacidity,exchangeablealuminium,therewasalsonegativecorrelationbetweenCa-P,Al-P(exceptinyoungstandandhalf-maturestand),Fe-P,O-P,andtotalhydrolyticacidityrespectively.Forrhizospheresoil,thecorrelationcoefficientbetweenCa-P,O-Pandtotalhydrolyticaciditydecreased,respectively,asstandagesupandthatbetweenFe-Pandexchangeacidity,exchangeablealuminiumincreased,respectively,asstandagesgrew.Fornon-rhizospheresoil,therewasnotsignificantcorrelationbetweensoilacidityandvariousformsofinorganicphosphorusandorganicphosphorus,respective

简介：为高度产生降级的土壤的可持续性的一个重要因素是监视即时并且写实地反映不同收割系统在土壤上强加的变化的工具的使用。为了选择，在甘蔗(SaccharumofficinarumL.)玷污优秀指示物变量在管理辨别完成敏感的标准到管理惯例和在季节之间一致性的生产区域，十件合成土壤样品(010厘米)在器官的甘蔗(OS)的耕作下面从区域在2006年3月(旱季)在2005年7月(雨季)并且再被收集，绿甘蔗(GS)，烧的甘蔗(BS)并且从一个邻近的本国的森林(NF)在UsinaTriunfo的区域，BocadaMata，Alagoas，巴西。微生物引起的biomass-C(MBC)，全部的器官的C(TOC)，表示为水解作用，水马厩土壤总数(MWD)的吝啬的重量直径，和水马厩宏的百分比聚集的荧光黄diacetate(食物及药品管理局)(PWSA)的率的土壤酶活动被分析。尽管MBC和TOC比在栽培区域在NF是更高的，没有差别在在三个甘蔗系统之间的这些C水池被观察。到地点管理的食物及药品管理局的反应依赖于采样时间。在多雨的时期，这项活动跟随了顺序：NF>OS>GS>BS在旱季，仅仅NF不同于另外的处理。不管采样时间，MWD和PWSA在顺序NF减少了>OS=GS>BS。变量MWD和PWSA为不管怎样在地点管理历史之间区别是相当敏感的采样季节。

简介：A21-daylaboratoryincubationexperimentwasconductedtoinvestigatetheimpactofpesticides(Triazophos,ButachlorandJinggangmycin)onapaddyfieldsoilhealthundercontrolledmoisture(floodedsoil)andtemperature(25℃)conditions.Theelectrontransportsystem(ETS)/dehydrogenaseactivitydisplayedanegativecorrelationwithpesticidesconcentrations,andtheactivitywasaffectedadverselyastheconcentrationofthepesticidesincreased.Thehigherdosesofpesticides,5and10foldsfieldrates,significantlyinhibitedETSactivity,whilelowerratesfailedtoproduceanysignificantreducingeffectagainstthecontrol.TherelativetoxicitylevelofpesticidesindecreasingtheETSactivitywasinthefollowingorder;Triazophos>Jinggangmycin>Butachlor,irrespectiveoftheirratesofapplication.Thepesticidescausedanimprovementinthesoilphenolcontentanditincreasedwithincreasingtheconcentrationofagrochemicals.Thepesticideincorporationdidnotproduceanysignificantchangeinsoilproteincontent.TheresponseofbiomassphospholipidcontentwasnearlysimilartoETSactivity.ThephospholipidcontentwasdecreasedwiththeadditionofpesticidesinthegivenorderofTriazophos>Jinggangmy-cin>Butachlor;andthetoxicitywasintheorder:10FR(timesoffieldrate)>5FR~>1.0FR>0.5FR>control.

简介：从最近在中国的香港以传统的方式进行的土壤调查基于遗产土壤数据，印射方法的数字土壤被使用为香港的山区生产土壤订购信息。二建模方法(决定树分析和线性判别式分析)被使用，并且他们的应用被比较。更多努力被放在为当模特儿选择土壤covariates上。首先，变化(ANOVA)的分析被用来测试在土壤订单之间的地面属性的变化。然后，一个逐步的过程被用来为线性判别式分析选择土壤covariates，并且一个向后的搬迁过程被开发为树建模选择土壤covariates。同时，印射的土壤上的ANOVA结果，以及我们的知识和经验，也为为树建模选择土壤covariates被考虑。二个线性判别式模型和四个树模型最后被建立，并且他们的预言表演用一条多重jackknifing途径被验证。结果证明在ANOVA结果上造的判别式模型最好表演了，由造由的判别式模型列在后面逐步，树模型由向后的搬迁过程，在印射的土壤上根据知识和经验造的树模型，和树造了自动地造的模型。结果强调了在为印射的土壤当模特儿选择土壤covariates的重要性，并且建议了在这研究使用选择土壤covariates的方法的实用性。最好的判别式模型最后被选择为这个区域印射土壤订单，并且确认结果显示出有的那张因此生产的土壤顺序地图高精确性。

简介：

简介：Itisgenerallyacceptedthatthecompositionsandpropertiesofsoilorganicmatter（SOM）arein?uencedbymanyfactors.InordertorevealtheeffectsofsoiltextureoncharacteristicsanddynamicsofSOManditssub-fraction,humicacid（HA）,alongtwosoilpro?les,ayellowsoilpro?leandapurplishsoilpro?le,underthesameclimateandvegetationconditionsweredetermined.Resultsindicatethatthedecompositionandhumi?cationdegreesofSOMandHAofthepurplishsoilsarehigherthanthoseofthecorrespondingyellowsoilsindicatedbyA/O–AratiosofHAs,TOCsandHAyieldsofbulksoilsamples,nevertheless,thedevelopmentdegreeofthepurplishsoilislowerthanthatoftheyellowsoil.ThevariationsofE4/E6ratiosofHAsalongthesoilpro?lesindicatetheoverallmolecularsizesofHAsdecreaseddownwardalongthesoilpro?les.A/O–AratiosofHAsdecreaseddownwardalongboththesoilpro?lesindicatethathumi?cationprocessesdecreasedownwardalongboththesoilpro?les.LeachingofSOMshowssigni?canteffectsonthedistributionandcharacteristicsofHAsintheyellowsoilpro?lebutthepurplishsoilpro?le,whichisconsistentwiththehigherhydrophobicityofHAsinpurplishsoils,showsthatthedistributioncharacteristicsofSOMalongthesoilpro?lesareacomplexresultofthecombinationofsoiltextureandcharacteristicsofSOMitself.TheremarkablydifferentsandcontentsareconcludedtentativelyasoneofreasonstothedifferentdistributionsanddynamicsofHAsalongthesoilpro?les,however,toprofoundlyunderstandtheevolutionandtransportofSOMalongsoilpro?lesneedsmoreresearches.

简介：Anintactalkalimarshsoil(MS)coreandanagriculturesoil(AS)corewerestudiedbythesimulatedtestinordertogetthecomparisonofthenutrientsretentioninalkaliMSandAS.ThesoilcoresextractedfromtheXianghaiWetland,westernJilinProvince,China,wereleachedwithsolutioncontainedcarbon,nitrogenandphosphorus.Thentheeffluentwaterfromtheoutletsofsoilcorewithdifferentdepthswasmeasured,includingchemicaloxygendemand(COD),totalphosphorus(TP),phosphate(PO3-4-P)andnitrogenexistedasnitrate(NO-3-N),nitrite(NO-2-N)andammonianitrogen(NH+4-N)andthetotalnitrogen(TN)intheeffluentwater.CODandTParedecreasedwiththedepth,thechangingtrendsofTN,NO-3-NandNH+4-NcontentsaresimilartoCODandTP,whereasNO-2-NinbothMSandASeffluenthavealittletransitionat40cmdepth.ItissimilarefficiencyofMStoASinsignificantlycuttingdownCOD,TP,PO3-4-P,TN,NO-3-N,NH+4-NandNO-2-Ninnutrientwater.ThefunctionofMSwouldbesameefficiencyofthenutrientsretentionastheAS.AlthoughtheSOMandpHhavesomeimpactsonnutrientsretentioninthesoil,theMSwithhighersoilorganicmatter(SOM)andpHhavethesameeffluentwaterastheASwiththelowerSOMandpHatthedepthof60cm,thebottomofthesoilcores.

简介：有在直径的30m和在高度的6m的大规模桶基础被用作风汽轮机的基础。宽浅的基础与有到直径的高度的高比率的传统的桶基础不同。新类型基础的cover-load-bearing模式能抵抗更多的外部装载。完成适用的模式，在桶内的泥泞土壤应该被增强，它将改进土壤力量并且转变为土壤和基础整个部分抵抗外部装载。增强方法的真空和电镀物品渗透的土壤在实验被使用。结果证明泥泞土壤的适用的行为被否定压力和电镀物品渗透的效果有效地改进，并且有更好的力量的改进泥泞土壤能和桶基础工作，意味着新桶基础的最高封面的适用模式被完成。在增强过程的土壤期间，基础向下移动了，即，基础的解决几乎在真空和电镀物品渗透的方法引起的预装的过程期间被完成。

简介：composted污水污泥(CS)并且热地的年度增加的效果在80t弄干污水污泥(TS)哈?1在半干旱的条件下面在一个地实验在土壤化学药品性质上被调查三年。腐殖的酸()从CS，TS，和unamended由常规过程孤立(那么)并且污泥修改了土壤被分析为元素(C，H，N，S和O)并且酸的功能的组(羧基、酉分)并且由紫外可见，红外线的Fourier变换和荧光光谱学。关于CS，TS有内容，更大的干燥的事，全部的器官的C，全部的N和C/N比率和更小的灰满足的类似的pH和全部的P和K和电的电导率。有CS和TS的改正在土壤性质导致了很多修正，包括pH，电的传导性，全部的器官的C，全部的N，和可得到的P的增加。CS--哈有的更大的O，全部的酸味，carboxyl，并且酉分哦比TS组织内容和H内容--哈。CS--哈并且TS--哈有的更大的N和S内容，更小的C，O和酸的功能的组内容，和更低的芳香的polycondensation和humification度比那么--哈。修改土壤--显示出C，H，N和比大的S内容那么--哈，建议污泥有部分被合并到土壤。这些效果与增加污泥应用的数字是更明显的。

简介：Apotexperimentwasconductedtoinvestigatetheeffectsofvarioussoiltreatmentsonthegrowthofvetivergrass(Vetiveriazizanioides(L.)Nash)withtheobjectiveofformulatingappropriatesoilmediaforuseinsulfide-bearingminedareas.Anacidicminesiteacidsulfatesoil(pH2.8)wastreatedwithdifferentsoilconditionerformulaincludinghydratedlime,redmud(bauxiteresidues),zeoliticrockpowder,biosolidsandacompoundfertilizer.Soilstreatedwithredmudandhydratedlimecorrectedsoilacidityandreducedoreliminatedmetaltoxicityenablingtheestablishmentofvetivergrass.Althoughover-limingaffectedgrowth,someseedlingsofvetiversurvivedtheinitialstrongalkalineconditions.Additionofappropriateamountsofzeoliticrockpowderalsoenhancedgrowth,butover-applicationcauseddetrimentaleffects.Inthisexperiment,soilmediumwiththebestgrowthperformanceofvetiverwas50gofredmud,10goflime,30gofzeoliticrockpowderand30gofbiosolidswith2000gofminesoils(100%survivalratewiththegreatestbiomassandnumberofnewshoots),butaddingachemicalfertilizertothismediaadverselyimpactedplantgrowth.Inaddition,ahighapplicationrateofbiosolidsresultedinpoorergrowthofvetiver,comparedtoamoderateapplicationrate.

简介：城市的土壤，与城市的发展一起形成，有土壤的唯一的性质器官的碳。根据地调查和实验室分析，玷污Kaifeng的器官的碳(SOC)城市被学习，并且结果证明SOC的特征在在城市的区域的功能区域之中是不同的不仅，而且在城市的区域和郊区之间。在表层土的SOC的顺序是工业区域>娱乐区域>交通区域>文化/教育的区域>居住/行政的区域。土壤的密度在表层土和侧面的器官的碳(SOCD)跟随了娱乐区域的订单>工业区域>交通区域>文化/教育的区域>居住/行政的区域，和文化/教育的区域s>交通区域>工业区域>娱乐区域>行政/居住的区域分别地。在表层土和侧面的SOCD从城市的区域沿着横断线减少了到郊区，城市的区域有2.53褶层在表层土和1.56褶层的更多的SOCD在侧面的更多的SOCD比郊区分别地。SOC与深度减少了并且主要在030厘米的范围以内被散布。在城市的区域的SOC的变化在郊区是比那更复杂的。

简介：Byusingnutritionaldiagnosisofcitrusleavesanddeterminingsoilmicronutrients,therelationshipbetweensoilmicronutrientsandcitrusgrowthinsouthernChinahasbeenstudied.Studiesshowedthattherewasasignificantpositivecorrelationbetweenavailablemicronutrients(suchasZn,Mo,Cu)inthesoilandthecorrespondingnutrientsincitrusleaves.Thus,onecanroughlylearnofthesufficiencyordeficiencyofcertainnutrientsinsoilsbyanalyzingcitrusleaves.RationalsprayofZnBorMofertilizernotonlyimprovedcitrusyieldsbutalsoincreasedthetotalsugarofSatsumamandarinandofXinhuiorangeby2.9and17.2%respectivelycomparedwiththecontrol.SprayingMofertilizerincreasedthevitaminCcontentofSatsumamandarinjuiceby4.7%-8.4%,maturatedfruits7-10daysearlierandgavethepeelabrightercolor.TheultramicroscopiccharacteristicsofZn-deficientcitrusleaveswereinvestigatedunderanelectronmicroscope.ResultsshowedthattheZn-deficientleafcellwascharacterizedmainlybypoorcytoplasm,endoplasmicreticulaandribosomesandbybigstarchgrainsinthechloroplast.AsaresultofsprayingZnfertilizerthestructureofthecellreturnedtonormal,thecytoplasmbecamerichandtheamountofchloroplastincreased.Therealsoappearedagreatdealofmultiformendoplasmicreticula,thuspromotingthephotosynthesisofZn-deficientplants.Thisprovidesacytologico-theoreticalbasisforfertilizationofhigh-yieldingcitrustrees.

简介：ThecomponentsofexpansivesoilwereanalyzedwithEDAX,anditisshownthatthemaincontentsofexpansivesoilinthenorthernHubeihavesomesignificanteffectsonengineeringpropertiesofexpansivesoil.Furthermore,thesoilmodifiedbylimehasanobviousincreaseofCa2+andanimprovementofconnectionsbetweengranulessoastoreducetheexpansibilityandcontractilityofsoil.Anditalsohasabettereffectonthemodifiedexpansivesoilthantheonemodifiedbypulverizedfuelash.

简介：在中国的黄土高原上，干燥土壤层可以由于过量蒸发形成，导致蝗虫(Robiniapseudoacacia)承受的黑色的降级。为了更好设法，预测包含黑蝗虫，这研究被打算调查黑蝗虫蒸发率的反应玷污在黄土高原上用二代表性的土壤(卢拇的泥土和沙的沃土)由气象学的因素影响了的水可获得性。四个土壤水内容为在开始户外的壶然后在一个控制气候的房间种的黑蝗虫幼苗被维持，由弄干或灌溉壶。在两环境，每日的蒸发率被力量功能与空气温度并且由逻辑功能有关引用土壤水分蒸发蒸腾损失总量(et0)。蒸发率比在卢拇的黏土更产生处于在沙的沃土的气象学的条件的变化。在浇得好的处理的蒸发率为比在卢拇的黏土在沙的沃土种的黑蝗虫是更大的。规范的蒸发率由et0是未受影响的直到土壤水内容的批评价值(c)被达到；c价值为卢拇的黏土显著地减少了，但是当et0增加了时，为沙的沃土土壤显著地增加了。这些建议黑蝗虫的蒸发特征上的气象学的条件的效果依赖于土壤质地。

简介：A15-yearfertilizationexperimentwithdifferentapplicationsofinorganicN,PandKfertilizersandfarmyardmanure(M)wasconductedtostudytheyieldandsoilresponsestolong-termfertilizationatQiyang,HunanProvince,China.Averagegrainyieldsofwheatandcorn(1672and5111kgha-1,respectively)forthetreatmentNPKMweresignificantlyhigherthanthose(405and310kgha-1)oftheunfertilizedcontrolandsingleinorganicfertilizertreatments.Comparedwiththecorrespondinginitialvaluesoftheexperiment,alltreatmentsshowedayielddeclineof9to111kgha-1year-1inwheatand35to260kgha-1year-1incorn,respectively,andasignificantpHdeclineof0.07to0.12pHyear?1,exceptforthetreatmentsPKandNPKM.Afterlong-termfertilization,thesoilorganicC,soilavailableP,exchangeableCa2+andMg2+andavailableCu2+andZn2+contentswerehigherinthetreatmentNPKMthaninthetreatmentsappliedwithinorganicfertilizeronly.ComparedtothetreatmentNPK,thetreatmentNPKM,wheremanurepartiallyreplacedinorganicN,hadapositiveimpactonarrestingthedeclineofsoilpH.Thisimprovedgrainyieldsofwheatandcorn,suggestingthatapplicationofNPKfertilizerincombinationwithfarmyardmanureisimportanttomaintainsoilfertilityandbufferingcapacityinredsoil.

简介：DNAisthegeneticmaterialofvariousorganisms.ExtracellularDNAadsorbedorboundonsurface-activeparticlesinsoilshasbeenshowntopersistforlongperiodsagainstnucleasesdegradationandstillretaintheabilitytotransformcompetentcells.ThispaperreviewssomerecentadvancesonthebindingandtransformationofextracellularDNAinsoils,whichisfundamentaltounderstandingthenatureofthesoil,regulatingbiodiversity,andassessingtheriskofreleasinggeneticallyengineeredmicroorganisms(GEMs)aswellasbeinghelpfulfordevelopmentofthegeneticevolutionaltheoryofbacteria.Severalinfluencingfactors,suchassoilpH,ionicstrength,soilsurfaceproperties,andcharacteristicsoftheDNApolymer,arediscussed.Todate,theunderstandingofthetypeofmolecularbindingsitesandtheconformationofadsorbedandboundDNAtosoilparticlesisstillinitsinfancy.