矿物固铵能力对铵离子在土壤中转化过程的影响Ⅰ．不同矿物类型土壤、不同C／N和K￣（＋）的存在对铵转化过程的影响

EFFECT OF AMMONIUM FIXATION CAPACITY ON TRANSFORMATION OF NH IN SOILSⅠ.EFFECT OF DIFFERENT C/N RATIOS AND PRESENCE OF K￣(+) ON TRANSFORMATION OF NH IN SOILS

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。

This rescarch studies the transformation of NH_4 as related to the fixation and release ofNH_4,different C/N ratios,compositions of day minerals and amounts of K￣(+)aded in two differentsoils,in which NH_4 was added before.In high C/N ratios,a large amount of NH_4-N added was directlyused by the mieroorganisms in the acid soil which is primarily composed of 1:1 day mincrals,but a larg1amount of NH_4 -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 NH_4-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.