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As a result of intensive greenhouse vegetable production in northern China,the potential risk of nitrogen (N) fertilizer over-applied is increasingly apparent and is threatening ecosystem and the sustainability of food production.An experiment was carried out in Shouguang,Shangdong Province,China to evaluate agronomic benefit and soil quality under different N applications,including the conventional chemical N rate (1 000 kg N ha-1 season-1,N1),70% of N1 (N2),70% of N1 + maize straw (N3),50% of N1 + maize straw + drip irrigation (N4),and 0% of N1 (N0),during two successive growing seasons of autumn-winter (AW) and winter-spring (WS).The maximum yields for N4 were 1.1 and 1.0 times greater than those for N1 in the AW and WS seasons,respectively.N agronomic efficiency (AEN) and apparent N recovery efficiency (REN) were greatest with the N4.A significant relationship was found between soil NO3--N content and electrical conductivity (EC) (R2=0.61 in the AW season and R2 =0.29 in the WS season) Reducing N fertilizer decreased soil NO3--N accumulation (20.9%-37.8% reduction in the AW season and 11.7% 20.1% reduction in the WS season) relative to the accumulation observed for N1 within the 0-100 cm soil layer.Soil urease and invertase activities were not significantly different among N treatments.The N4 treatment would be practical for reducing excess N input and maintaining the sustainability of greenhouse-based intensive vegetable systems in Shouguang.