包膜与氢醌结合对尿素释放及水解的影响

Effect of coating and hydroquinone incorporation on urea-N release and its hydrolysis.

通过探讨尿素和脲酶抑制剂氢醌被共同包被后二者在土壤中的溶出行为及其对尿素水解的控制,阐明此类肥料减缓尿素水解的机理,为此类肥料的开发和农业应用提供一定的理论依据。采用室内摸拟培养的方法开展:(1)尿素和脲酶抑制剂氢醌被共同包被后二者在土壤中的溶出行为。(2)添加氢醌尿素、包膜型尿素、尿素和脲酶抑制剂氢醌被共同包被后尿素在土壤中的水解特征。尿素和氢醌共包被肥料中尿素和氢醌的溶出高峰期同步,但氢醌从包膜中溶出的速率明显快于尿素;氢醌的添加减缓了尿素的水解进程,包膜型肥料释放到土壤中的尿素没有立即完全水解,而是发生了明显的水解滞后现象,但尿素水解速率的最大值明显高于尿素溶出速率的最大值,与包膜型肥料相比,尿素与氢醌共包被的尿素水解也有明显的滞后现象但其尿素水解速率的高峰值明显低于尿素溶出速率的高峰值;尿素在土壤中的水解速率决定性地影响着土壤pH的变化。包膜与氢醌的结合更加有效地控制了尿素的水解过程,尿素和氢醌的同时缓慢溶出使尿素的水解过程更加平缓,有效避免了尿素水解的激增现象,此种肥料的施用有利于减缓NH3的毒害及NH3的挥发损失。

Aimed to clarify release behavior and urea hydrolysis process of coated urea and hydroquinone fertilizer, two incubation experiments were conducted. The results indicated that urea and hydroquinone exhibited synchronous release fastigium and com- pared to urea, hydroquinone showed higher release rate. Urea hydrolysis was retarded when added with Hydroquinone and coated with film. Urea hydrolysis rate was faster than urea release rate in coated urea while Coated with film retarded urea hydrolysis sig- nificantly and its urea hydrolysis rate was slower than release rate. Hydrolysis rate of urea affected soil pH. Coating and hydro- quinone incorporation effectively retarded urea hydrolysis. The simultaneous release of urea and hydroquinone avoided sudden in- crease of NH3 formation and N volatilization loss.