秸秆还田配施稳定性氮肥对麦玉轮作水氮利用的影响

为探究秸秆还田配施稳定性氮肥对关中地区麦玉轮作体系作物生长及水氮利用的综合影响，并确定合理的高产高效施肥管理措施，设置两种秸秆还田模式(秸秆不还田、秸秆全量还田)和两种施氮措施(常规尿素和减量施用稳定性氮肥),以无秸秆还田且不施肥作为对照，共5个处理，研究分析作物产量、地上部生物量、土壤氨挥发累积量、土壤含水率、土壤硝态氮残留量及水氮利用效率。结果表明：秸秆还田配施氮肥会分别显著提高夏玉米和冬小麦产量28.03%～39.63%和90.10%～112.52%、地上部生物量27.88%～34.00%和78.96%～107.64%;施用稳定性氮肥较施用常规尿素分别降低夏玉米季和冬小麦季全生育期土壤氨挥发累积量50.18%～59.32%和68.21%～73.43%;秸秆还田会显著提高夏玉米季0～10 cm土壤含水率6.29%～21.38%,显著提高冬小麦季0～10 cm土壤含水率6.80%～25.06%;相同施肥措施下，秸秆还田会显著降低夏玉米与冬小麦收获期0～100 cm土壤NO^-₃-N残留量7.34%～10.78%和6.57%～11.24%,在相...

Effects of Straw Returning and Application of Stable Nitrogen Fertilizer on Water and Nitrogen Use Efficiencies of Wheat Maize Rotation

In order to explore the comprehensive impact of straw returning with stable nitrogen fertilizer on crop growth and water and nitrogen utilization of wheat maize rotation system in Guanzhong region, and determine reasonable high-yield and efficient fertilization management measures, two straw returning modes (no straw returning, full straw returning) and two nitrogen application measures (conventional urea and reduced application of stable nitrogen fertilizer) were set up in a completely random combination, and straw free returning and no fertilization were set as control, a total of five treatments were set to study and analyze crop yield, aboveground biomass, soil ammonia volatilization accumulation, soil moisture content, soil nitrate nitrogen residue and water and nitrogen utilization efficiency. The results showed that straw returning to the field could significantly increase the yield of summer maize and winter wheat by 28.03%~39.63% and 90.10%~112.52%, respectively, and increase the aboveground biomass by 27.88%~34.00% and 78.96%~107.64%. The application of stable nitrogen fertilizer reduced the soil ammonia volatilization accumulation by 50.18%~59.32% and 68.21%~73.43% during the whole growth period of summer maize season and winter wheat season respectively compared with the application of conventional urea. Straw returning to the field could significantly increase the soil moisture content of 0~10cm soil in summer maize season by 6.29%~21.38%, and that of 0~10cm soil in winter wheat season by 6.80%~25.06%. Under the same fertilization measures, straw returning to the field could significantly reduce the NO-3N residues in the 0~100cm soil of summer maize and winter wheat at harvest time by 7.34%~10.78% and 6.57%~11.24%. Under the same straw returning mode, the application of stable nitrogen fertilizer could significantly reduce the NO-3N residues in the 0~100cm soil of summer maize and winter wheat at harvest time by 28.96%~31.63% and 4.16%~9.54% compared with that of application of urea. Under the same fertilization measures, straw returning significantly improved water use efficiency, nitrogen partial productivity and nitrogen agronomic efficiency in summer maize season and winter wheat season by 4.55%~7.85%, 5.79%~12.08%, 25.22%~41.43% and 7.36%~9.73%, 2.25%~14.38% and 4.33%~30.35%. Under the same straw returning mode, the application of stable nitrogen fertilizer significantly improved the partial productivity of nitrogen fertilizer, agronomic efficiency of nitrogen fertilizer, nitrogen absorption efficiency, nitrogen recovery efficiency of 43.75%~52.29%,42.01%~60.39%, 62.07%~66.67%, 52.50%~72.73% and 21.93%~36.41%, 11.37%~39.14%,50.67%~53.85%, 60.00%~64.15%, respectively, in summer maize season and winter wheat. Therefore, straw returning with stable nitrogen fertilizer would significantly improve water and nitrogen use efficiency of wheat maize rotation system, reduce nitrogen volatilization loss and nitrogen leaching risk. Based on comprehensive consideration, 180kg/hm2 stable nitrogen fertilizer and 150kg/hm2 stable nitrogen fertilizer were reasonable fertilization measures for realizing high yield and efficiency of summer maize and winter wheat in Guanzhong area.