土壤团聚体的经典文章
92JOURNALOFSUSTAINABLEAGRICULTURE
betweenandConsequently,(3)reducesaunitvolumetheopportunityofwaterandfortheCa-Nasurfaceareaofthegypsumparticles,forreclamation.increasingflowratesreducesexchangetheefficiency(Nadlerofetusingal.,gypsum1996a).OrganicMatter
controversial.
Theroleoforganicmatter(OM)withregardtoaggregatestabilityisstilllates,Additiondispersionaspartates,oforganiclactates,anionsand(fulvates,acetates)tocitrates,soilsuspensionsoxalates,tartrates,increasessalicy-clayPiccolo1990;KretzschmarFrenkeland(ShanmuganathanMbagwu,etal.,1992;1989;andOades,1983;DurginandChaney,1984;HeilKosmasandandMoustakas,1990;Goldbergetal.,1995).fulvicVandenetal.,Broek1993;(1989)ItamiobservedandSposito,Kyuma,1993a,b;Tarchitzkyetal.,1993;that1995;andHeilandSposito,whereasandcitricacidstoclaysuspensionsnotablyadditionofsmallamountsofeffect.aromaticacids(salicylicandp-hydroxybenzoic)increasedhaveclayaflocculatingdispersion,substances.
VisserandCaillier(1988)alsoshowedthedispersiveeffectofhumictweenOnHamblinorganictheothermatterhand,therehavebeennumerouspositivecorrelationsbe-FortúnFierrosandandFortún,Davies,and1989);1977;waterChaneyHamblinstableandandaggregates,WSA((Greenland,1971;Swift,Greenland,1984;1977(allthreecitedinsonThisViqueira,apparentcontradiction1989;MbagwuonandtheeffectsPiccolo,of1989;BenitoOMcomesandFortúnRuedaandDíaz-frometal.,1989).ConsideringofOMwithstabilityparameterssuchasWSA,andDispersedthecompari-concludedthatincreasingWSAincreasesaggregatestability,Clay,itcanDC.beclaydecreasesdispersionthatOMseparateaggregatedecreasesincreasesstability.aggregateaggregateTheparadoxstability,stability.ConsideringthatincreasingcanitbecanbeconcludedthatOMstability,aggregatestabilityinmacro-aggregatestabilityunderstoodandmicro-aggregateinpartifwewhereasDCaswereflectsproposeinthispaper.WSAreflectsmacro-aggregatestabilitytradiction.Therearemorelikelymicro-aggregatethreemainhypothesisstability.
toexplaintheapparentstability,effectmacro-aggregateFirst,bothstabilitystabilityparametersemphasizedifferentaspectscon-ofclay,anionanddependsinparticular,onthetypeontheofsizeunionandofbetweenmicro-aggregatestability.Second,thethethehumicsubstancesandtheparticlesislongerandandbindthanthemtheclayedge,itwillorganicattachtoanions.theedgesOnlyofifseveraltheorganicclaylevels,Shanmuganathanmacro-aggregatesandtogetherOades,(Durginandmicro-aggregates.1983).Third,andChaney,OM1984;Emerson,1977;Thus,actsdifferentlyorganicbondsatthestabi-
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