以太湖地区三种类型水稻土为对象进行的研究表明:(1)风干土淹水培养后,固定态铵平均增加17ppm,相当于交换性铵增量的28%。似应将培养后固定态铵的增量与交换性铵增量之和计为土壤氮素的矿化量。(2)田间微区试验中,耕层以下土壤所供应的氮量占稻田土壤供氮量的16—49%,平均30%。(3)根据所得结果,讨论了用培养法预测稻田土壤供氮量中存在的问题。 The study on three types of paddy soils in the Taihu Lake region showed that: (1) After the aerated soil was flooded, the fixed ammonium increased by an average of 17ppm, equivalent to 28% of the exchangeable ammonium. It seems that the amount of ammonium nitrogen should be considered as the amount of mineralization of soil nitrogen after the cultivation. (2) In the field trial, the amount of nitrogen supplied by the soil below the tillage layer accounts for 16-49% of the nitrogen supply to paddy soil, an average of 30%. (3) Based on the results obtained, the problems existing in soil nitrogen supply of paddy fields were discussed using culture method.