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应用土柱模拟法和~(15)N示踪技术研究了长期淹水和严重渗漏条件下水稻的生长和氮肥的吸收与转化。结果表明，两种水分条件下，水稻根系生长量和地上部干物质积累量明显不同。水稻在淹水条件下因根系生长受阻，氮积累在拔节后明显变缓；而渗漏条件下水稻对氮的吸收在孕穗期仍保持较高水平。前者对肥料氮的利用率较后者显著地低，且土壤矿化氮在所吸收的氮中的贡献率也相对较高。这与水稻在两种水分管理条件下的生长状况和氮在两种情形下的转化特点密切相关。本试验条件下，水稻于拔节后对土壤矿化氮的吸收数量明显增加，似有脱肥现象，因此，应提倡追施孕穗肥。
Soil column simulation and ~ (15) N tracing techniques were used to study the growth and nitrogen uptake and transformation of rice under long-term flooding and severe seepage conditions. The results showed that under both water conditions, the root growth and dry matter accumulation of shoots were significantly different. Under flooded conditions, rice plants were obstructed by root growth, and nitrogen accumulation obviously slowed down after jointing. However, the nitrogen uptake by rice remained a relatively high level at booting stage. The former has a significantly lower utilization rate of fertilizer nitrogen than the latter, and the contribution of soil mineralized nitrogen to the absorbed nitrogen is also relatively high. This is closely related to the growth status of rice under two water management conditions and the transformation characteristics of nitrogen in two situations. Under the conditions of this experiment, the amount of mineralized N absorbed by rice increased obviously after jointing, which seems to be due to the phenomenon of removing fertilizer. Therefore, we should advocate topdressing booting fertilizer.