Liu Churong, Liu Hongrun, Liu Xueqing, Li Gang, Zhang Yushi, Zhang Mingcai, Li Zhaohu
State Key Laboratory of Plant Environmental Resilience, College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China; College of Natural Resources and Environment, Joint Institute for Environmental Research and Education, South China Agricultural University, Guangzhou, 10642, China.
State Key Laboratory of Plant Environmental Resilience, College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China.
Environ Res. 2023 Nov 1;236(Pt 1):116761. doi: 10.1016/j.envres.2023.116761. Epub 2023 Jul 27.
Excessive nitrogen (N) fertilization in agroecological systems increases nitrous oxide (NO) emissions. 3,4-dimethylpyrazole phosphate (DMPP) is used to mitigate NO losses. The influence of DMPP efficiency on NO mitigation was clearly affected by spatiotemporal heterogeneity. Using field and incubation experiments combined with metagenomic sequencing, we aimed to investigate DMPP efficiency and the underlying microbial mechanisms in dark-brown (Siping, SP), fluvo-aquic (Cangzhou, CZ; Xinxiang, XX), and red soil (Wenzhou, WZ) from diverse climatic zones. In the field experiments, the DMPP efficiency in NO mitigation ranged from 51.6% to 89.9%, in the order of XX, CZ, SP, and WZ. The DMPP efficiency in the incubation experiments ranged from 58.3% to 93.9%, and the order of efficiency from the highest to lowest was the same as that of the field experiments. Soil organic matter, total N, pH, texture, and taxonomic and functional α-diversity were important soil environment and microbial factors for DMPP efficiency. DMPP significantly enriched ammonia-oxidizing archaea (AOA) and nitrite-oxidizing bacteria (NOB), which promoted N-cycling with low NO emissions. Random forest (RF) and regression analyses found that an AOA (Nitrosocosmicus) and NOB (Nitrospina) demonstrated important and positive correlation with DMPP efficiency. Moreover, genes associated with carbohydrate metabolism were important for DMPP efficiency and could influenced N-cycling and DMPP metabolism. The similar DMPP efficiency indicated that the variation in DMPP efficiency was significantly due to soil physicochemical and microbial variations. In conclusion, filling the knowledge gap regarding the response of DMPP efficiency to abiotic and biotic factors could be beneficial in DMPP applications, and in adapting more efficient strategies to improve DMPP efficiency and mitigate NO emissions in multiple regions.
农业生态系统中过量施氮会增加一氧化二氮（N₂O）排放。3,4 - 二甲基吡唑磷酸盐（DMPP）用于减少N₂O损失。DMPP效率对N₂O减排的影响明显受到时空异质性的影响。通过田间和培养实验结合宏基因组测序，我们旨在研究来自不同气候区的暗棕壤（四平，SP）、潮土（沧州，CZ；新乡，XX）和红壤（温州，WZ）中DMPP的效率及其潜在的微生物机制。在田间实验中，DMPP在N₂O减排方面的效率在51.6%至89.9%之间，顺序为XX、CZ、SP和WZ。培养实验中DMPP的效率在58.3%至93.9%之间，效率从高到低的顺序与田间实验相同。土壤有机质、全氮、pH、质地以及分类和功能α多样性是影响DMPP效率的重要土壤环境和微生物因素。DMPP显著富集了氨氧化古菌（AOA）和亚硝酸盐氧化细菌（NOB），促进了氮循环且N₂O排放较低。随机森林（RF）和回归分析发现，一种AOA（亚硝化宇宙菌属）和NOB（硝化刺菌属）与DMPP效率呈重要正相关。此外，与碳水化合物代谢相关的基因对DMPP效率很重要，并且可能影响氮循环和DMPP代谢。相似的DMPP效率表明，DMPP效率的变化显著归因于土壤理化性质和微生物的变化。总之，填补关于DMPP效率对非生物和生物因素响应的知识空白，可能有利于DMPP的应用，并有助于采用更有效的策略来提高DMPP效率并减少多个地区的N₂O排放。
