【摘要】 用采自江苏省主要水稻土种和少数南方省份的水稻土１５个。盆栽试验研究表明：（１）淹水条件下土壤矿物对施入的肥料铵以及土壤氮矿化铵具有一定的固定能力，但不同土壤之间差异很大，其固定量受矿物组成、粘粒含量、石灰性反应等因素影响；（２）大部分被固定的铵在多数土壤上可以重新释放出来被水稻吸收，但能否全部重新释放则与粘土矿物组成有关。被蛭石固定的难以释放，而被水云母、蒙脱石固定的容易释放；（３）被固定铵的释放高峰与水稻吸氮高峰基本一致；（４）在盆栽条件下由矿物固定的按所提供的氮占水稻吸氮总量中的比例，在吸氮高峰期可达１．４％～８９．６％。更多还原

【Abstract】 A pot experiment was conducted to exame the mineral fixed ammonium and its availabilityto rice. Fifteen paddy soils collected from 7 provinces in southen China were used. Results indicated: a. Allsoils used fixed considerable amount of NH from both fertillzer and mineralized NH, but gave diverseNH -fixing capacity,depending on soil mineral conposition, clay content and lime reaction; b. Most ofthe newly fixed NH was released during rice growth. However, weather all of the newly fixed NH be-ing released depended on clay mlneral composition. NH fixed by venniculite was more difficult to be re-leased than by illite and montmorillonite; c. Releasing peak of fixed NH was coincident with the peak ofnitrogen uptake of rice; d. Mineral fixed NH contributed 1.4%～89.6% to the nitrogen taken up by rice.更多还原