水肥耦合条件下作物产量、水分利用和根系吸氮的试验研究

Field Test and Study on Yield, Water Use and N Uptake Under Varied Irrigation and Fertilizer in Crops

根据 1998～ 2 0 0 0年两年在北京市水科所永乐店节水灌溉中心开展的冬小麦、夏玉米水肥耦合的田间试验成果的分析研究表明 ,氮肥效益的发挥与农田水分状况密切相关 ,低供水水平时 (本研究中为冬小麦仅灌拔节水的节水灌溉处理 ) ,肥料的增产效益十分显著 ,但氮肥贡献率随施肥量的增加而呈递减的趋势。不同的分析方法都表明 ,在永乐店节水灌溉中心 ,冬小麦施尿素 40 0 kg/ hm2 和 2 0 0 kg/ hm2 两个施肥水平的试验处理所获得的水 (肥 )分生产率最高 (在不同农田供水状况下 ) ,由于两者的水分生产率差异不大 ,为提高施肥效率 ,建议在生产上考虑选择2 0 0 kg/ hm2 的施肥方案较合理。

In order to develope an optimum combination of water and fertilizer for winter wheat and summer corn, a field experimental research was carried out at Yongledian Water Saving Irrigation Station in Beijing from 1998 to 2000. The effect of irrigation regimes and N application on yield, dry matter production, water productivity and N uptake was tested and analized. Nitrogen production efficiency was greatly related to soil moisture condition. At low water supplying levels(irrigating only at stem clongation stage), the highest fertilizer contribution ratio was obtained. Nitrogen production efficiency is decreasing with more fertilizer applied in all treatments. The highest water productivity was obtained under N 2 treatments and N 1 treatments. N 1 nitrogen treatment(e.i., 200 kg/hm 2) in production management was proposed considering both the cost of nitrogen fertilizer input and nitrogen production efficiency.