设施菜田不同施氮处理对硝酸盐迁移和积累的影响

在设施菜地条件下,研究了氮肥减施及配施抑制剂处理在黄瓜生长期对土壤NO3--N迁移累积的影响。结果表明,氮肥减施处理可显著降低土壤表层和整个土体的NO3--N含量。常规施氮量时0~40 cm土层的NO3--N含量均高于其它处理,减氮30%后0~40 cm土层未出现NO3--N显著积累现象;氮肥配施抑制剂处理不同程度降低了土壤NO3--N含量,且抑制硝态氮向下层土壤淋失,其中抑制剂组合的效果最好。氮肥配施抑制剂,可以有效控制NO3--N在土壤和植物体内的过量累积,减少硝态氮淋溶损失。

Effects of Nitrogen Fertilization on Nitrate Transformation and Accumulation in Greenhouse Vegetable Fields

A field experiment was conducted under protected cultivation condition to examine the effects of reduced N fertilizer and combined with the inhibitors on the accumulation of NO3——N in soil during the growing stages of cucumber plantation.Results showed that reduction of N fertilization could significantly decreased NO3——N content of surface soil and other layers of the soil profile.Nitrate contents in 0-40 cm soil layers were greater under the conventional N application than in the other treatments.As N input was reduced by 30%,NO3——N accumulation was not significant in 0-40 cm soil layers.Nitrogen fertilizer combined with inhibitor could decrease the content and leaching loss of NO3——N,of which the effect of NBPT combined with DCD treatment on NO3——N accumulation was the best.Nitrogen fertilization combined with inhibitors could effectively control the over-accumulation of nitrate in both soil and test vegetable,and reduce the leaching loss of NO3——N.