高寒半干旱区水肥耦合对西芹收获期硝酸盐效应研究

为了探讨西芹水肥耦合作用,采用三因素(氮、磷和水)五水平(因子水平为-1.682、-1,0,1,1.682)二次通用旋转组合设计,在冀西北高寒半干旱区开展了水肥耦合对西芹硝酸盐效应的旱棚试验研究。结果表明,在该试验条件下水分对硝酸盐降低的作用最大,磷肥次之,氮肥最小;从卫生学角度考虑水肥耦合的硝酸盐效应最佳顺序依次为:中水中肥效应最佳,高水高肥次之,低水低肥较差;水肥交互耦合效应大小顺序是磷水耦合>氮水耦合>氮磷耦合。在西芹水肥管理方案中,硝酸盐不同取值区间内三因子的变化范围均相同,体现了因子间相互替代效应。从卫生学角度考虑,以中水中肥为宜。

Effect of nitrogen,phosphorus and water coupling on nitrate content of celery in harvesting time

To seek for effect of water and fertilizer coupling on celery,with 3 factors(N,P,W) and 5 levels(factors levels including-1.682,-1,0,1,1.682) of the secondary regression of orthogonal block design,artificial water control experiments in the shed of rain-free condition were conducted in semiarid cold region of northwest of Hebei to study effect of water and fertilizer coupling on nitrate content of celery.Results showed that irrigation quantity was the chiefly factor to affect nitrate content of celery,phosphorus quantity was the secondly factor,nitrogen quantity was the thirdly factor.Based on the public heath index,nitrate effect was the better in the condition of middle level water and fertilizer,but which was the lowest in low level water and low fertilizer,on which was between the two in high level water and high fertilizer.The effect order of interaction was phosphorus and water coupling>nitrogen and water coupling>nitrogen and phosphorus coupling.In the water and fertilizer management strategy,the value interval of the three factors was the same to the different nitrate content interval,which indicated the substituting effect among the factors.It was a mostly feasible condition to the middle level water and fertilizer from the public heath index.