Soil Aggregate Stability(14)

土壤团聚体的经典文章

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sphericalahigherbindingshapeofsurfacetheFetopolymers;whatmeansahighertouchingsurface,sopolymersHowever,that(asMcNealFeCl)wereetal.claybetter(1968)particles.

stabilizingandShainbergthanAletpolymers,al.(1987)foundthatFe3thethestabilizingeffectwasrelatedtothechargeonthepolymersandconcludedandnottoidesIntotalconclusion,amountextracted.

thereisaluminumonmicro-aggregateresolved.ismoreeffectivestability,goodevidenceofthepositiveeffectofthesesquiox-inaggregationeventhoughofsoiltheparticlesdebateofiswhethernotcompletelyironorExternalFactorsClimate

typeClimateizeandisoneofthesoil-formingfactorsthatstronglyinfluencesthesoilorganicandaggregatemattersummarizethedegreeofsoilaggregation.CarterandStewart(1996)character-storage.theBlackmanimpactofvaryingclimateonsoilaggregationandrelationtostabilitytheweatherandconditionsBullocket(1992)thatal.(1988)observedaseasonalvariationintheaffectaggregatepresentedseasonalprocessesining-thawingWatercontentincyclesadynamiccycles)changesway.Ininfluence(wetting-dryingcycles)andairstability.

temperature(freez-thetheformationanddestructionofsoilstructurelarytheactionasafield,soilissubjectedtomultiplewettinganddryingandresultevaporation.oftheprocessesTheseofcycles,condensation,affectedbyrainfall,airtemperature,irrigation,capil-tureAfterfreezing-thawinginduceBraggaboutyearstheofinvestigation,cycles.

thereisstilldiversityofopinioninthelitera-isingattributed(1985)effectofthesecyclesonsoilstructuralstability.LynchandtoandmainlyOades(1993)mentionedthatthesoilaggregateformationsuspensionandthawing.Grantofclay,Syntheticphysicalforcessuchaswettinganddryingandfreez-siltandaggregateswereformedbywettinganddryingasomethesoils,andBlackmoresand(Singeretal.,1992;Amézketaetal.,1995).usuallyvertisols,(1991)presentedandWenkeandGrant(1994)observedthat‘‘self-mulching.’’

courseofwettinganddrying.Thethebehaviorabilitytoofre-aggregatethesesoilstheirwasclaycalledinandSoulidesandAllison(1961),Tisdallmacro-aggregateMullaetal.(1988),stability.(1992)foundetal.(1978),Lehrschetal.(1991),However,thatUtomowettingandandDexterdrying(1982),cyclesdecreasedstablemacro-aggregation.andBarzegaretal.Singer(1995)etfoundal.(1992)thatthesesuggestedcyclesresultedDexteretal.thatwettinginwater-and

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