【摘要】 研究了田间条件下控释肥料氮的释放速率与水稻吸收氮量之间的关系。结果表明 ,控释肥料氮的释放速率在水稻生育前期高 ,但随着时间的进程而逐渐降低。水稻从 70日型控释肥料中吸收的氮遵循三次曲线 ,因此 70日型控释肥料能够满足水稻本田生长期对氮的需要。施用控释肥料的水层含氮量极低 ,且无可见的水藻生长 ;而施尿素的水层则尿素N和NH+4 N含量高 ,水藻活动繁茂 ,滞留于水层的肥料氮 5～ 6d内迅速地降至无氮对照水平 ,氨的挥发损失和氮的反硝化损失大。控释肥料氮的利用率高达 72 3% ,比尿素高出 36 5个百分点。更多还原

【Abstract】 Field experiment was conducted in paddy soil to determine the relationship between N release from controlled release fertilizer and N uptake by rice plants N release rate of controlled release fertilizer was higher during the early growing period of rice, but gradually decreased with time The cumulative N release reached about 80% of the total N content of fertilizer at around 70 day after application or when cumulative air temperature had reached about 2000℃ Nitrogen uptake from the fertilizer followed a cubic curve Therefore, the fertilizer can meet the N requirements of two line system late hybrid rice throughout the whole growing period There were lower N concentrations of the water and hardly any algae observed in the plots where controlled release fertilizer applied Higher urea N and ammonium N concentration of the water in the paddy field after urea applied indicates the greater N losses from NH 3 volatilization and denitrification As high as 72 3% in late rice of fertilizer N were recovered by the rice plant at harvest (grain+straw) with the 70 day type controlled release fertilizer Controlled release fertilizer increased efficiency of nitrogen use and minimized environmental pollution更多还原