简介:Theobjectiveofthisstudywastoinvestigatetheef-fectsofearthwormdensityontheavailabilityofnutrientsandheavymetalsinmetalcontaminatedsoils.Pb/Znminetailingsweremixedthroughlywitharedyellowpodzolicsoilattheratio(w/w)of75:25.Earthworms(Pheretimasp.)wereintroducedtothemixtureatfourdifferentdensities,zero,three,sixandnineindividualsperpotplantedwithryegrass(Loliunmultiflorum).Theresultsindicatedthatearthwormactivitysignificantlyen-hancedryegrassshootbiomass.However,asdenserearthwormpopulationwasintroduced,shootbiomasstendedtodecrease.EarthwormactivitysignificantlyincreasedsoilpHandavailabilityofN,PandKinthetailingsandsoilmixture.TherewasageneraltendencythatuptakeofZnbyryegrassincreasedafterearthworminoculation,althoughtheincreaseinextractableZnintailingsandsoilmixturewasnotsignificant.Onthecontrary,thereseemedtobealoweruptakeofPbbyryegrassunderearthworminoclation,despitethefactthathigherextractablePbconcentrationswereobserved.Thepresentprojectindicatedthattheimprovedgrowthofryegrasswasduetoimprovednutrientavailabilityandothersoilconditions,byinoculationofearthwormsatanappropriaterate.Furtherstudiesareneededtoillustratetherelationshipbe-tweenmetalavailabilityandearthwormactivityinthefield.