【摘要】 研究着重了解ＮＨ_４－Ｎ肥施入不同矿物类型土壤后，由于不同Ｃ／Ｎ和粘土矿物组成的不同以及Ｋ￣（＋）的加入，导致ＮＨ＿４向ＮＯ＿３的转化和矿物的固定与释放所具有的不同特点。在Ｃ／Ｎ高的情况下，施入的ＮＨ＿４－Ｎ对于１：１型粘土矿物为主的酸性土壤来说，主要以ＮＨ_４的形态直接被微生物大量利用，而在以２：１型粘土矿物为主的中性土壤上，施入的ＮＨ_４先被矿物晶层大量固定，然后再释放出来被微生物所利用。当施入大量钾时，即使在Ｃ／Ｎ较高的情况下，被矿物晶层先固定的ＮＨ＿４也难以大量释放。更多还原

【Abstract】 This rescarch studies the transformation of NH₄ as related to the fixation and release ofNH₄,different C/N ratios,compositions of day minerals and amounts of K￣（+）aded in two differentsoils,in which NH₄ was added before.In high C/N ratios,a large amount of NH₄-N added was directlyused by the mieroorganisms in the acid soil which is primarily composed of 1:1 day mincrals,but a larg1amount of NH₄ -N added was fixed by mineral interlayers at first, which could be used by themlcroorganisms when released aftemards, in the neutral soil which is primarily composed of 2:1 dayminerals.The NH₄-N fixed in the mineral interlayers before could not release in large quantity when alarge amount ofK￣（+） was added even in high C/N ratios.更多还原