新型硝化抑制剂NP对黑土无机氮转化的影响

研究新型硝化抑制剂2-氯-6(三氯甲基)吡啶微胶囊(NP)对黑土中无机氮(NH4+-N、NO3--N、NO2--N))转化的影响,从而筛选出适宜黑土的最佳施用量,可为进一步的生产实践提供理论支持。采用室内培养的试验方法,在土壤含水量为田间持水量的65%、温度25℃条件下,设不施肥、单施尿素、尿素+0.5%硝化抑制剂、尿素+1%硝化抑制剂、尿素+3%硝化抑制剂5个处理,其中,施肥处理的N使用量均为0.6 g/kg(土),硝化抑制剂的使用量为纯N用量的比例,测定了NP不同用量对土壤NH4+-N、NO3--N和NO2--N含量以及p H值的影响,并评价了NP的抑制效果。结果表明:施用NP处理的土壤NH4+-N含量均显著单施尿素处理,NO3--N和NO2--N含量均显著单施尿素处理;土壤NH4+-N含量与土壤p H值呈正相关;NP不同用量处理的土壤NH4+-N、NO3--N和NO2--N含量以及p H值差异均不显著;NP显著抑制了土壤NH4+-N向NO2--N的转化,进而降低了土壤NO3--N的含量。综合评价,推荐NP的使用量为纯N用量的0.5%。

Effects of New Nitrification Inhibitor on Inorganic Nitrogen Transformation in Black Soil

A simulating experiment was carried out to study the effects of different concentrations of nitri-fication inhibitor 2-chloro-(thichloro methyl) pyridine (NP) on inorganic nitrogen transformation in black soil,and the best application was screened to provide references for agricultural practice. The soil mois-ture was 65% of field moisture capacity and the temperature was 25℃,the appraise of different concen-trations of NP (0.5%, 1%, 3%) on inorganic nitrogen forms (NH4+-N, NO3--N, NO2--N) and pH in black soil were compared. Then the inhibition effect of NP was evaluated. The results showed that com-pared to fertilization of urea treatment, the contents of soil ammonium nitrogen in NP was higher, while nitrate and nitrite nitrogen concentrations were significantly lower. No significant difference was observed in NH4+-N, NO3--N, NO2--N and pH (P﹤0.05) . New nitrification inhibitor NP significantly inhibited the transformation ammonium nitrogen to nitrate nitrogen in the soil,and reduced the content of nitrate nitro-gen in the soil,comprehensive evaluation recommended dosage was 0.5%.