中文摘要：

采用室内培养试验探讨了钾素、尿素与有机物料或双氰胺配施对土壤中NH4＋-N和NO3^--N含量变化及相关的脲酶、转化酶的影响。试验结果表明,尿素与双氰胺配施延缓硝化作用的进行,有效地降低土壤中NO3^--N的积累和维持土壤中较高的NH4^＋-N含量,而尿素配施有机物料对土壤NO3^--N和NH4^＋-N含量的影响与单施尿素处理间没有显著差异。土壤铵态氮含量随施钾量的增加而增加,而硝态氮含量则呈下降趋势。钾对土壤脲酶和转化酶活性没有明显的影响,但是配施有机物料处理的脲酶和转化酶活性显著高于单施尿素或尿素配施DCD。

英文摘要：

A soil incubation experiment was carried out to explore the effect of combined application of potassium, urea with DCD or different organic materials on NO3^--N and NH4^＋-N content in vegetable soils, and the relationship between urease and the activities of invertase. The results showed that lower NO3^--N content and higher NH4^＋-N content in soil was observed in the treatment of combined application urea with DCD, but addition of organic manure to urea did not show notable effect on NO3-N and NH4^＋-N content in the soil. The activities of soil urease and invertase were significantly higher in the combined application of organic manure with urea than that of single urea or urea with DCD treatments, but insignificant difference was found among different potassium levels.