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为比较硝化抑制剂双氰胺、硫代硫酸钾对土壤氮的硝化抑制效果,明确其对土壤氮转化作用效应,采用室内培养试验方法,研究了双氰胺、硫代硫酸钾及其配施对土壤矿质氮动态变化、硝化作用及氮回收率的影响。结果表明,单施氮肥土壤硝化作用活跃,77.7%的化肥氮以铵态氮形式从矿质氮库消失,其中56.6%的氮形成硝态氮。氮肥配施双氰胺、硫代硫酸钾分别显著降低矿质氮库铵态氮消失量74.1%(P<0.01)和16.6%(P<0.05),同时配施双氰胺和硫代硫酸钾处理铵态氮出现增加现象。氮肥配施双氰胺及同时配施2种抑制剂均不同程度地抑制氮的硝化作用,抑制率分别为35.5%~98.7%和82.2%~103.5%,硝化作用延滞时间均在20 d以上。氮肥配施硫代硫酸钾的硝化抑制率为1.6%~62.6%,硝化作用延滞时间为10 d。双氰胺硝化抑制效应优于硫代硫酸钾,且2种抑制剂同时配施作用效果优于其单独施用。施用硫代硫酸钾可促进土壤NO2--N积累,双氰胺可抑制NO2--N生成。氮肥配施双氰胺及同时配施两种抑制剂处理显著增加土壤矿质氮含量、降低其他去向氮含量同时显著提高土壤矿质氮回收率14.7%(P<0.05)和12.0%(P<0.05)。总体上,抑制剂双氰胺在铵态氮转化、硝化作用抑制及提高矿质氮回收率等方面作用效果均优于硫代硫酸钾,硫代硫酸钾与双氰胺配施在硝化抑制作用方面具有协同效应。该研究结果可为双氰胺、硫代硫酸钾在农田氮素面源污染控制中的应用提供科学依据,但对2种抑制剂硝化抑制特性的全面了解,尚需在田间试验条件下进行进一步的研究和验证。
In order to compare the nitrification inhibitory effect of nitrification inhibitor dicyandiamide and potassium thiosulfate on soil nitrogen and clarify its effect on soil nitrogen conversion, the effects of dicyandiamide, potassium thiosulfate and their combination Effects of soil mineral nitrogen dynamic changes, nitrification and nitrogen recovery. The results showed that the soil with single nitrogen application was active in nitrification. 77.7% of the fertilizer nitrogen disappeared from the mineral nitrogen pool with ammonium nitrogen, of which 56.6% nitrogen formed nitrate nitrogen. Nitrogen fertilizer with dicyandiamide and potassium thiosulfate significantly decreased the amounts of ammonium nitrogen in mineral N reservoir by 74.1% (P <0.01) and 16.6% (P <0.05), respectively. Meanwhile, dicyandiamide and potassium thiosulfate Ammonium nitrogen increased phenomenon. Nitrogen fertilization with dicyandiamide and simultaneous application of two inhibitors all inhibited the nitrification of nitrogen to varying degrees, with the inhibition rates of 35.5% -98.7% and 82.2% -103.5%, respectively, and the nitrification delay lag above 20 days. Nitrification with potassium thiosulfate nitrification inhibition rate of 1.6% to 62.6%, nitrification delay of 10 d. Dicyandiamide nitrification inhibitory effect is better than potassium thiosulfate, and the two inhibitors at the same time with the effect is better than the single application. Potassium thiosulfate promoted soil NO2 - N accumulation and dicyandiamide inhibited NO2 - N production. Nitrogen fertilizer with dicyandiamide and simultaneous application of two inhibitors significantly increased soil mineral nitrogen content, reduced other nitrogen removal levels and significantly increased soil mineral nitrogen recovery by 14.7% (P <0.05) and 12.0% (P <0.05), respectively. . In general, the effect of dicyandiamide, an inhibitor of ammonium dithiamide, on the conversion of ammonium nitrogen, the inhibition of nitrification and the recovery of mineral nitrogen were better than that of potassium thiosulfate. Potassium thiosulfate and dicyandiamide were applied in the inhibition of nitrification Has a synergistic effect. The results of this study may provide a scientific basis for the application of dicyandiamide and potassium thiosulfate in the control of nitrogenous non-point source pollution in farmland. However, the thorough understanding of the inhibitory properties of two inhibitors on nitrification need to be further carried out under the field test conditions Research and verification.