不同肥料用量及配比对设施土壤硝态氮含量的影响

通过大田实验研究不同氮磷钾肥用量、氮磷钾配施、有机无机肥配施对设施土壤硝态氮残留的影响.结果表明:设施土壤中硝态氮质量比随着氮肥用量的增加迅速增加,并且随着种植年限增加不断累加;而适量的磷肥和钾肥有利于降低硝态氮的质量比.与不施肥处理相比,单施有机肥时土壤中残留的硝态氮较少,而单施化肥土壤中的硝态氮残留量明显增加,掺沙后促进了土壤有机氮和有机肥的矿化,使硝态氮累积量进一步增加.化肥与有机肥配施时,土壤的硝态氮质量比因作物而异,可能由于作物的生育期和需肥量不同导致的.

The effects of fertilizer rate and their ratios on soil nitrate content in solar greenhouse

A field experiment was carried out to study the effects of N,P,K fertilizer rates ,their ratios and combination of organic fertilizer and chemical fertilizer on soil residue nitrate content after harvesting in solar greenhouse. Results showed that soil nitrate content increased quickly with increase of N fertilizer rate. Moreover, soil nitrate was increasing with the plant year progress. Nevertheless, application of appropriate amount P and K fertilizer was beneficial to the reduction of soil nitrate content after harvesting. Compared with no fertilizer treatment, the residue nitrate content was less with organic fertilizer only. However, the significant increase with chemical fertilizer only was observed. Further increase of nitrate accumulation was occurred in the treatment of addition sand due to the promotion of mineralization of soil organic nitrogen and organic fertilizer. Soil residue nitrate content was varied with kind of crops with treatments of combination of chemical fertilizer and organic fertilizer. This may be caused by the difference in crops＇ growth stage and their requirements of fertilizer.