硝化抑制剂与不同氮肥配施对土壤硝化过程的抑制效果OA北大核心CSTPCD

To clarify the effects of DMPP(3,4-dimethylpyrazole phosphate)combined with different nitrogen fertilizers under different soil conditions,the effects of nitrification inhibitor DMPP combined with urea-ammonium nitrogen fertilizer,compound fertilizer,ammonium sulfate-nitrate and oxalamide on nitrogen conversion and ammonia volatilization in soils with pH 5.48(south paddy soil)and pH 8.25(north salinized fluvo-aquic soil)were studied via soil microcosm incubation in the laboratory.The results showed that the combined applications of DMPP with different types of nitrogen fertilizer could inhibit the conversion of soil NH4-N to NO3-N under different soil conditions,and the effects in alkaline soil were better than those in acidic soil.At the end of culture,in acidic soil,the nitrification inhibition effects of DMPP with different fertilizers were of compound fertilizer＞urea-ammonium nitrogen fertilizer＞oxalamide＞ammonium sulfate-nitrate,with nitrification inhibition rates of 64.5％,54.1％,40.4％and 13.2％,respectively,while in alkaline soil were of urea-ammonium nitrogen fertilizer(69.6％)＞compound fertilizer(58.3％)＞oxalamidide(49.9％)＞ammonium sulfate-nitrate(26.2％).The accumulated ammonia volatilization in alkaline soil was significantly higher than that in acidic soil under different fertilizer treatments,and the combined application of DMPP with compound fertilizer significantly increased the accumulated ammonia volatilization under different soil conditions,but the combined applications of DMPP with urea-ammonium nitrogen fertilizer,ammonium sulfur nitrate and oxalamide had no significant effect on soil accumulated ammonia volatilization.In general,the combined applications of different nitrogen fertilizers with DMPP can inhibit soil nitrification process,and the effects were better in alkaline soil,but the combined application of DMPP with conventional balanced compound fertilizer would significantly increase the risk of soil ammonia volatilization,which is also related to fertilizer type,DMPP added amount and soil pH.In conclusion,the combination applications of different fertilizers with nitrification inhibitors according to different soil conditions can better play the role of nitrification inhibitors,which has guiding significance for stabilized fertilizers production based on different nitrogen forms.