Influence of Sludge Incineration Ash on Ryegrass Growth and Soil Phosphorus Status

(整期优先)网络出版时间:2019-01-11
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Phosphorus(P)isalimitedresourcethatcouldbedepleted.Consequently,recyclingthePcontainedinsewagesludge,includingsewagesludgeincinerationash(SIA),fromwastewatertreatmentplantsisapossibilitytobeexplored.Agreenhouseexperimentusingannualryegrass(LoliummultiflorumL.)wasperformedwithanexperimentaldesignofthreecompletelyrandomizedblocksoftwosoilsand29treatments:onecontrolwithoutPandtwolevelsof9and26kgtotalPha-1from14differentsources:twelveSIAs(notcontaminatedbytracemetals)fromtheUSandCanada,onecommercialsyntheticfertilizer(triplesuperphosphate(TSP)),andonecommercialrockphosphate(RP).Higherryegrassbiomasslevelswereachievedatthehigherfertilizationrate(26kgtotalPha-1)andwhenusingtheSIAswiththehighestPsolubilitypercentage(PSP)(≥54%oftotalP).ThebiomassincreasesfollowingSIAapplicationwereashighas29%and59%morethanthecontrolforthesandyloamandclayeysoil,respectively,but40%lessthaninTSPforbothsoils.AsimilarbehaviorwasobservedforPuptake,withamaximumincreaseof26%fortheclayeysoil,and165%forthesandyloamsoil.TheryegrassbiomassandPuptakeincreasesduetoSIAapplicationwerelargerthanthoseduetoRPapplicationintheclayeysoil,butsimilartothoseinthesandyloamsoil.TheSIAswithaPSPof≥54%significantlyincreasedsoilavailablePstocksandsaturation.Accordingtoourfindings,weconcludethattheSIAsfrommunicipalandagrifoodindustrieshaveapotentialforPagriculturalrecycling,buttheirefficienciesvary.