水氮耦合对膜下滴灌玉米产量和水氮利用的影响

【目的】提高黑龙江西部地区玉米水肥利用率及产量,探索不同水肥配比下玉米氮素吸收、利用与分配规律。【方法】设置3个灌溉定额水平(200、400、600 m3/hm~2)以及5个施氮水平(0、150、200、250、300 kg/hm~2),研究分析了不同水肥处理下玉米干物质积累、氮素分配、氮素吸收效率、氮收获指数、氮肥偏生产力以及氮肥农学生产效率等指标。【结果】增加施氮量可以显著提高玉米产量、干物质和氮素积累量,水分不足会抑制产量、干物质和氮素的累积,但灌水定额过高会降低氮收获指数。W400N250处理产量、干物质量、氮素积累量、氮肥利用率、氮收获指数、氮肥农学效率、水分利用效率均为最高,分别较其他处理高了0.71%～45.28%、1.07%～48.87%、9.54%～70.61%、2.63%～37.65%、3.19%～10.38%、0.84%～32.80%、1.27%～43.24%。【结论】在膜下滴灌方式下,黑龙江西部地区玉米最佳灌水量为400 m3/hm~2,最佳施氮量为250 kg/hm~2。

Nitrogen-water Coupling Affects Nitrogen Utilization and Yield of Film-mulched Maize under Drip Irrigation

【Objective】Soil water and nutrients combine to modulate physical and biochemical processes in soil and in this paper we studied the impact of water-nitrogen coupling on yield and nitrogen use efficiency of a filmmulched maize field irrigated with drip irrigation.【Method】The field experiment was conducted in western Heilongjiang province and we compared three irrigations: 200 m3/hm~2, 400 m3/hm~2 and 600 m3/hm~2, and five nitrogen fertilizer applications: 0 kg/hm~2, 150 kg/hm~2, 200 kg/hm~2, 250 kg/hm~2, 300 kg/hm~2, with each treatment having three replicas. In each treatment, we measured the dry biomass accumulation, uptake and distribution of nitrogen by the plant, nitrogen uptake efficiency, nitrogen harvest index, the partial productivity of nitrogen fertilizer and the efficiency of nitrogen fertilizer.【Result】Increasing nitrogen application increased the accumulations of dry matter and nitrogen significantly, but a shortage of soil water could reduce dry matter accumulation. Increasing the amount of irrigation water enhanced nitrogen harvest index. The yield, dry matter accumulation, nitrogen accumulation amount, nitrogen fertilizer utilization rate, nitrogen harvest index, the efficiency of nitrogen fertilizer, water use efficiency under the treatment of W400 + N250 were higher than those under other treatments by0.71%～45.28%,1.07%～48.87%,9.54%～70.61%,2.63%～37.65%,3.19%～10.38%,0.84%～32.80%,1.27%～ 43.24%,respectively.【Conclusion】Under drip irrigation coupled with film mulching, the optimal amount of irrigation for maize in western Heilongjiang was 400 m3/hm~2 and the nitrogen application was 250 kg/hm~2.