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在我国内蒙古自治区赤峰市农牧交错区研究了不同耕作方式及不同施氮量对小麦氮肥吸收利用和产量的影响.结果表明:长期实施保护性耕作使小麦对氮素的利用率提高3%～4%,减轻氮肥对农田环境的污染;保护性耕作有利于促进小麦对氮素的吸收,提高小麦产量.当施氮量由120kg·hm-2增加到360kg·hm-2时,小麦对氮素的吸收利用由36.5%降低为26%;氮素损失增加约5%,对应的氮素损失量则从60kg·hm-2增加到约200kg·hm-2,对环境的污染明显增加.小麦对上季残留氮素的利用受耕作方式影响较小,受上季施氮量影响较大,总体趋势为施氮量越高,小麦利用率越低,损失越多.经过两季小麦种植后,小麦-土壤系统回收的总氮素比例约为44%～50%,其中土壤残留氮素约占施氮量的13%～18%.
The effects of different tillage patterns and nitrogen application rate on nitrogen use efficiency and yield of wheat were studied in the ecotone of agriculture and animal husbandry in Chifeng City, Inner Mongolia Autonomous Region. The results showed that the long-term conservation tillage enhanced the utilization of nitrogen in wheat by 3% 4%, reducing the nitrogen pollution on farmland environment; conservation tillage is conducive to promoting nitrogen uptake by wheat and increasing wheat yield .When nitrogen application rate increased from 120kg · hm-2 to 360kg · hm-2, Nitrogen loss increased by about 5% from 36.5% to 26%, and the corresponding nitrogen loss increased from 60kg · hm-2 to about 200kg · hm-2, which significantly increased the environmental pollution. The use of residual nitrogen in the last season was less affected by the tillage system and was more affected by the amount of nitrogen application in the previous season. The general trend was that the higher the amount of nitrogen application, the lower the utilization rate of wheat and the more losses. After two seasons of wheat planting , And the total nitrogen recovered by the wheat-soil system is about 44% -50%. The residual nitrogen in soil accounts for about 13% -18% of the nitrogen application.