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本文讨论长期高量偏施氮素化肥的高产稻田氮肥施用与作物产量、作物对养分吸收利用之间的关系。研究结果表明：化学氮肥施用量（养分量，下同）300kg／ha·yr.,作物增产显著，每公斤氮增产13．5kg粮食，氮素利用率达40．3％，省肥、经济、合理；施用量达450kg／ha·yr.,作物产量增长甚微；施用量达600kg／ha·yr.,每公斤氮只增产7．29kg粮食，氮肥利用率降至17．2％，水稻茎秆中含氮量大幅度增加，空秕率上升，千粒重下降，产量降低。太湖地区高产稻田目前稻麦产量为10-12t／ha水平时，氮素化肥施用量平均控制在375kg／ha·yr。左右为宜。与大面积生产相比，可节省氮肥20—30％。
This article discusses the relationship between nitrogen application and crop yield, crop uptake and utilization of nutrients in high-yielding paddy with long-term high Nm fertilization. The results showed that the application of chemical nitrogen fertilizer (nutrient content, the same below) 300kg / ha · yr., Crop yield significantly, per kilogram of nitrogen yield 13.5kg grain, nitrogen utilization rate of 40.3%, fertilizer, economy, The application rate was up to 450kg / ha · yr ·, crop yield increased little; the application rate was 600kg / ha · yr. Only 7.29kg grain yield per kilogram of nitrogen was increased, and the nitrogen use efficiency dropped to 17.2% In the culm, the nitrogen content increased greatly, the air-chestnut rate increased, the grain weight decreased, and the yield decreased. At present, when the rice-wheat yield is 10-12 t / ha in the high-yielding rice fields in Taihu Lake, the average N application rate is 375 kg / ha · yr. About appropriate. Compared with large-scale production, nitrogen fertilizer can save 20-30%.