Nitrogen fertilization promoted microbial growth and N2O emissions by increasing the abundance of nirS and nosZ denitrifiers in semiarid maize field

作者：Setor Kwami Fudjoe, Lingling Li, Sumera Anwar, Shi Shangli, Junhong Xie, Linlin Wang, Xie Lihua, Zhou Yongjie · 发表于：Frontiers in Microbiology · 年份：2023 · DOI：10.3389/fmicb.2023.1265562 · 被引用次数：47 · 研究领域：Soil Carbon and Nitrogen Dynamics、Plant nutrient uptake and metabolism、Wastewater Treatment and Nitrogen Removal

Nitrous oxide (N 2 O) emissions are a major source of gaseous nitrogen loss, causing environmental pollution. The low organic content in the Loess Plateau region, coupled with the high fertilizer demand of maize, further exacerbates these N losses. N fertilizers play a primary role in N 2 O emissions by influencing soil denitrifying bacteria, however, the underlying microbial mechanisms that contribute to N 2 O emissions have not been fully explored. Therefore, the research aimed to gain insights into the intricate relationships between N fertilization, soil denitrification, N 2 O emissions, potential denitrification activity (PDA), and maize nitrogen use efficiency (NUE) in semi-arid regions. Four nitrogen (N) fertilizer rates, namely N0, N1, N2, and N3 (representing 0, 100, 200, and 300 kg ha −1 yr. −1 , respectively) were applied to maize field. The cumulative N 2 O emissions were 32 and 33% higher under N2 and 37 and 39% higher under N3 in the 2020 and 2021, respectively, than the N0 treatment. N fertilization rates impacted the abundance, composition, and network of soil denitrifying communities ( nirS and nosZ ) in the bulk and rhizosphere soil. Additionally, within the nirS community, the genera Cupriavidus and Rhodanobacter were associated with N 2 O emissions. Conversely, in the nosZ denitrifier, the genera Azospirillum , Mesorhizobium , and Microvirga in the bulk and rhizosphere soil reduced N 2 O emissions. Further analysis using both random forest and structural e...