【摘要】 采用15N示踪和模拟土柱技术,对不同透水性土壤施用氮肥后水稻生育和氮肥利用率进行了研究。结果表明:土壤透水速率以20～30mm/d对水稻生育最为有利,完全不渗漏和透水速率超过40mm/d时,水稻分蘖明显减少,收获期干物质积累和子实产量仅为适宜透水率时的66 7%～93 4%和65 2%～93 8%。土壤透水性强烈影响水稻对氮肥的利用效率。土壤透水率在20～30mm/d时,水稻对氮的利用率超过60%,而不透水土壤和严重渗漏土壤的水稻对氮肥利用率仅为32 6%～44 1%,损失率达30 8%～46 0%。稻作期间田面水层和0～5cm土层pH与土壤透水率呈负相关,排水不良易引起氨挥发。日渗漏20～30mm可作为沿黄高产稻麦田培育的定量指标。更多还原

【Abstract】 The rice growth status and utilization ratio of nitrogen fertilizer under the condition of different soil permeability in the nethouse were investigated by 15N tracer and imitative soil column technique.The results showed that the soil with 20～30 mm/d of the leakage speed was of most favorable to rice growth.When the soil permeability was over 40 mm/d or 0 mm/d,the numbers of rice effective tillering decreased obviously,and the biological and economical yield at harvest period were 66.7%～93.4% and 65.2%～93.8% of the treatment in comparing with the optimum soil permeability,respectively.The utilization ratio of nitrogen fertilizer exceeded 60% when rice was planted in the soil with optimum permeability,but it was only 32.6%～44.1% when planted in the other soil and the N loss reached 30.8%～460%.The pH of surface soil(0～5 cm) and surface water was negatively correlated with soil permeability.Poor drainage was easy to result in more N loss by NO3 volatilization.20～30 mm/d of soil leakage speed could be considered as an quantitative index for high yield soil along the Yellow River.更多还原