简介：Potassiumchloride,Na-pyrophosphate,CuCl2,NH4-oxalate,dithionit-citrate-bicarbonate(DCB)andNa-citratesolutionswereemployedtoetractaluminum(Al)andiron(Fe)sequentiallyandseparatelyfrom15acidicsoilslocatedattheMangshanMountains,HunanProvince,China,ManyevidencesshowedthatseparatepyrophosphateextractedmainlyKCl-extractableAl,organo-AlcomplexesandsomeinorganicAlcompounds,whereasseparateCuCl2extractedKCl-extractableAlandsomeorgano-Alcomplexes,CuCl2extractedmuchlessamountsofAlthanpyrophosphatedidfromthesoils.SeparateoxalatedidnotextractallKCl-pyrophosphate-CuCl2-oxalateseuentiallyextractableAlandFe,Also,separateDCBdidnotextractallKCl-pyrophosphate-CuCl2-oxalate-DCBsequentiallyextractableAl.TheformsofAlextactedbyoxalateandDCBfromthesoilsweremajorlynoncrystalline.Theinterlayeredmaterialsof1.4-nmintergrademineralsofthesoilswereattributedmainlytohydroxyAlpolymers.

简介：MicrometeorologicalandmicroplotexperimentswereconductedinthefieldoffreshlyharvestedgreencaneinQueensland,Australia.ResultsshowedthathighammonialossoffertilizerNcouldoccurunderrelativelydryconditionswhenureaorcommercialproductofmixtureofureaandmuriateofpotashwereappliedtothesurfaceofsugarcanetrash.ThemoisturecontentinthetrashandthepHoffertilizerweretwoimportantfactorscontrollingtheprocessesofureahydrolysisandammoniavolatilization.MostoftheNinthesoilwastransformedtothenitratel-nitritefromafter70daysoffertilizerapplication.Nosignificantleachingwasfound.Urea-freeNfertilizershadhigherNrecoveriescomparedtourea-containingfertilizers.