NBPT与DMPP不同剂量组合对尿素氮转化的影响

采用室内模拟试验的方法,探讨了脲酶抑制剂N-丁基硫代磷酰三胺(NBPT)和硝化抑制剂3,4-二甲基吡唑磷酸盐(DMPP)的不同浓度组合对尿素氮转化的影响。结果表明,NBPT与DMPP不同浓度组合均不同程度的延缓了尿素的水解,使尿素N水解产物更加以NH4+-N形态保持在土壤中;延缓了硝化作用进程并减少了硝酸盐在土壤累积,在此基础上增加了土壤有效态N含量。综合不同浓度组合对尿素水解的抑制、土壤NH4+-N和NO3--N含量变化、硝化作用抑制效果、土壤有效态N水平等指标并结合成本考虑,NBPT和DMPP分别为0.1%和0.5%施氮量时为最适宜的组合。

Synergistic Effect of Different Doses of NBPT and DMPP on Urea-N Transformation

With the incubation test, the synergistic effect of different doses of N-(n-butyl) thiophosphoric trimide (NBPT) and 3,4-dimethyl pyrazole phosphate (DMPP) on urea-N transformation were studied. The results showed that all treatments with the combined application of NBPT and DMPP could delay the hydrolysis of urea effectively, keep a higher amount of soil ammonium, retard nitrification of soil ammonium and decrease the accumulation of soil nitrate, and increase the total amount of soil available N comparing with the control. The results indicated that the treatment with 0.1% NBPT and 0.5% DMPP was the best combination.