【摘要】 通过 6个氮水平小区试验 ,研究了不同氮肥用量对冬小麦氮肥利用率和土壤剖面 NO3 -- N动态分布的影响。结果表明 ,氮肥利用率有随施氮量的增加而递减的趋势 ;土壤剖面 NO3 -- N含量则有随氮肥施用量增加而增加的趋势 ,而在同一氮水平下 ,从土壤表层到深层 (10 0 cm) ,则有递减的趋势。在冬小麦生育期中 ,以开花期 80～ 10 0 cm土壤剖面累积的 NO3 -- N量最多 ,因此最有可能淋洗出根层 ,对地下水造成污染更多还原

【Abstract】 Based on the field experiments of six levels of nitrogen fertillzer applied to winter wheat,the effects of quantity on its utilization ratio and dynamic distribution of soil NO 3 - N were studied The results indicated that the nitrogen fertilizer utilization ratio reduced with increasiag amount of N fertilizer application.but on the contrast,the content of soil NO 3 - N increased with iucreasing amount of N fertilizer application ,and under the same level of nitrogen fertilizer,from topsoil to deep layer of soil (100 cm),the content of soil NO 3 - N was decreased According to the amount of NO 3 - N in the deep layer soil during the growth of winter wheat,the amount of NO 3 - N accumulated in the surface layzs of soil of 80 cm to 100 cm was the higbest so it was very easy to seep into ground water and pollute the environment.更多还原