酸性土壤覆盖了约50%的耕地,具有高N2O排放潜力。3,4-二甲基吡唑磷酸盐(DMPP)抑制土壤中的N2O排放;然而,其效率受酸度影响。石灰用于土壤调理,以改善酸度的影响。在本研究中,我们研究了石灰对DMPP抑制酸性土壤中N2O排放效率的影响及其机理。我们评估了石灰的影响,DMPP,增城(ZC)和韶关(SG)两种酸性土壤的联合施用及其微生物响应,广东省,中国。土壤经过四种处理:未石灰土壤(低土壤pH值)尿素(LU),未石灰土壤+尿素+DMPP(LD),石灰土壤(高土壤pH)+尿素(HU),和石灰土壤+尿素+DMPP(HD)用于分析矿物氮,N2O排放,以及全长16S和宏基因组测序。结果显示,HU显著降低并增加了ZC和SG的N2O排放17.8%和235.0%,分别,与LU相比。这是由N2O生产和消耗之间的权衡造成的。其中微生物群落和氮循环功能基因在不同的酸性土壤中显示出各种组成。LD将ZC中的N2O排放减少了23.5%,而SG下降了1.5%。有趣的是,在两种酸性土壤中使用石灰后,DMPP效率显着提高。与LU相比,HD显著减少了ZC和SG的N2O排放61.2%和48.5%,分别。通过施用石灰和DMPP观察到缓解效率的协同作用,这归因于主要硝化剂的变化和反硝化剂N2O消耗的增加。石灰和DMPP的联合应用是减少N2O的高效策略,可以确保酸性耕地土壤中的农业可持续性,同时对环境造成的破坏最小。
Acidic soils cover approximately 50 % of the arable land with high N2O emission potential. 3,4-dimethylpyrazole phosphate (DMPP) inhibits N2O emission from soils; however, its efficiency is affected by acidity. Liming is used for soil conditioning to ameliorate the effects of acidity. In the present study, we investigated the effects of liming on the efficiency of DMPP in inhibiting N2O emission in acidic soils and the mechanisms involved. We evaluated the impact of liming, DMPP, and combined application and its microbial responses in two acidic soils from Zengcheng (ZC) and Shaoguan (SG) City, Guangdong Province, China. Soils were subjected to four treatments: un-limed soil (low soil pH) + urea (LU), un-limed soil + urea + DMPP (LD), limed soil (high soil pH) + urea (HU), and limed soil + urea + DMPP (HD) for analyses of the mineral N, N2O emissions, and full-length 16S and metagenome sequencing. The results revealed that, HU significantly decreased and increased the N2O emission by 17.8 % and 235.0 % in ZC and SG, respectively, compared with LU. This was caused by a trade-off between N2O production and consumption after liming, where microbial communities and N-cycling functional genes show various compositions in different acidic soils. LD reduced N2O emission by 23.5 % in ZC, whereas decreased 1.5 % was observed in SG. Interestingly, DMPP efficiency considerably improved after liming in two acidic soils. Compared with LU, HD significantly reduced N2O emissions by 61.2 % and 48.5 % in ZC and SG, respectively. Synergy of mitigation efficiency was observed by lime and DMPP application, which was attributed to the changes in the dominant nitrifiers and the increase in N2O consumption by denitrifiers. The combined application of lime and DMPP is a high-efficiency strategy for N2O mitigation can ensure agricultural sustainability in acidic arable soils with minimal environmental damage.