DMPP对菜地土壤氮素淋失的影响研究

采用小粉土和青紫泥原状土柱种植青菜，研究了尿素添加DMPP（3．4-二甲基吡啶磷酸盐）硝化抑制剂对土壤氮素淋失的影响。结果表明．在60天内，与常规尿素相比，小粉土和青紫泥DMPP处理硝态氮的累积淋失量分别降低66．8％和69．4％，氨氮淋失量提高9．7％和6．7％，无机氮降低59．1％和63．0％；蔬菜收获后，土壤0～15cm层无机氮增高34．1％和28．2％，土壤中氮素纵向迁移降低。可见，DMPP抑制剂施入土壤具有显著的氨氧化抑制作用，延缓蔬菜地土壤氨氮向硝态氮的转化，减轻氮素向水体迁移的风险。使用硝化抑制剂DMPP，由于土壤对氨氮的强吸附特性．迁移总量低，不会对地下水造成污染的风险。

Effect of DMPP on Inorganic Nitrogen Leaching Loss from Vegetable Soil

In an undisturbed column experiment,the nitrogen leaching losses in the powder soil and blue clayey paddy soil was studied by applied urea with new nitrification inhibitor 3,4-dimethyl pyrazole phosphate(DMPP).The results showed that,within the 60 days of the experiment,in the powder soil and blue clayey paddy soil,the accumulative leaching losses of soil nitrate in treatment with DMPP were 66.8% and 69.4% lower,while ammonium-N were 9.7% and 6.7% higher than normal urea treatment,respectively,and the accumulative leaching losses of soil(ammonium nitrate)-N were 59.1% and 63.0% lower.After experiment,inorganic nitrogen content in the 0~15 cm layer soil were 28.2% and 34.1% larger,and the nitrogen vertical transfer was greatly declined.The fact that the application of DMPP could obviously decrease the nitrogen leaching losses from soil could contribute to the nitrification inhibitor effects of DMPP on the retard of ammonium nitrification for about 60 days.It is suggested that the DMPP could be used as an effective nitrification inhibitor to control the nitrate leaching losses and minimize the underground water pollution risk.