To evaluate the effect of a nitrification inhibitor on reducing N2O emissions from saline soils, we undertook a field plot experiment with three salinity levels (non-saline, NS = 0.21 dS m−1; low saline, LS = 1.02 dS m−1; and high saline, HS = 5.23 dS m−1), factorially combined with two nitrification inhibitor treatments (with and without DMPP (3,4-dimethylpyrazole phosphate)). The low saline soil had the highest N2O flux peak and its cumulative N2O emissions were 2.2-fold those of the non-saline soil and 3.1-fold those of the high saline soil. Low salinity strongly inhibited nitrite oxidation and only slightly inhibited ammonia oxidation, which resulted in a high accumulation of NO2−-N and high N2O emissions. The nitrification inhibitor DMPP reduced cumulative N2O emissions (p < 0.05) by 61% in non-saline soil (reduction of 88.3 mg N m−2) and by 75% in low saline soil (reduction of 239.8 mg N m−2). DMPP offsets low salinity-induced high N2O emissions by inhibiting ammonia oxidation.

中文翻译：

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硝化抑制剂 DMPP 抵消了土壤盐分引起的 N2O 排放增加

为了评估硝化抑制剂对减少盐渍土壤中 N2O 排放的影响，我们进行了三个盐度水平（非盐度，NS = 0.21 dS m-1；低盐度，LS = 1.02 dS m-1；低盐度，LS = 1.02 dS m-1；和高盐分，HS = 5.23 dS m-1)，因子结合两种硝化抑制剂处理（有和没有 DMPP（3,4-二甲基吡唑磷酸盐））。低盐分土壤的 N2O 通量峰值最高，其累积 N2O 排放量是非盐分土壤的 2.2 倍和高盐分土壤的 3.1 倍。低盐度强烈抑制亚硝酸盐氧化，仅轻微抑制氨氧化，导致 NO2--N 的高积累和高 N2O 排放。硝化抑制剂 DMPP 在非盐渍土壤中将 N2O 的累积排放量（p < 0.05）减少了 61%（减少了 88. 3 mg N m-2)，在低盐度土壤中降低 75%（减少 239.8 mg N m-2）。DMPP 通过抑制氨氧化来抵消低盐度引起的高 N2O 排放。