双氰胺和表面活性剂添加对沼液氮素形态变化的影响

为探究双氰胺和表面活性剂添加到沼液中对其氮素形态和含量的影响，通过室内模拟试验，设置单施沼液（对照）、沼液+8%双氰胺（DCD）、沼液+16% DCD、沼液+表面活性剂、沼液+8% DCD+表面活性剂、沼液+16% DCD+表面活性剂，共6个处理，在静置10、30 min和1、3、10、24、48 h时测定沼液中总氮（TN）、总凯氏氮（TKN）、铵态氮（NH₄⁺-N）、硝态氮（NO₃^--N）含量。结果表明：与对照单施沼液相比，沼液中添加8% DCD和16% DCD后，NH₄⁺-N浓度增加了0.74%~8.96%，TKN浓度增加了24.67~59.70 mg·L^-1，NO₃^--N浓度增加了13.42~145.88倍，且NH₄⁺-N、TKN、NO₃^--N浓度与DCD添加量呈正相关。表面活性剂添加对沼液氮素形态和浓度没有显著影响。研究结果可为提高抑制剂抑制效果和科学施用抑制剂提供数据支撑。

Effects of dicyandiamide and surfactant on nitrogen form dynamics in digested slurry

The aim of the present study was to explore the effects of dicyandiamide(DCD)and surfactant on the form and content of nitrogen in digested slurry, using a laboratory simulation experiment with different combinations of application of the treatments. Six treatments were used:single application of digested slurry, digested slurry+8%DCD, digested slurry+16%DCD, digested slurry+surfactant, digested slurry+8%DCD+surfactant, and digested slurry+16%DCD+sufactant. The total nitrogen(TN), total Kjeldahl nitrogen(TKN), ammonium nitrogen(NH₄⁺-N), and nitrate nitrogen(NO₃^--N)content of digested slurry were measured at 10, 30 min, and 1, 3, 10, 24, 48 h. The results revealed that, in the digested slurry+8%DCD and digested slurry+16%DCD treatments, the concentrations of NH₄⁺-N, TKN, and NO₃^--N increased by 0.74%~8.96%, 24.67~59.70 mg·L^-1, 13.42~145.88 times, respectively, and the concentrations of all three increased with the quantity of DCD. The addition of surfactant had little effect on the form and concentration of nitrogen in digested slurry.