Nitrous oxide (N2O) reduction plays a crucial role in mitigating N2O emissions from terrestrial ecosystems, but the function and distribution pattern of nosZI- and nosZII-containing N2O reducers in different land use remains largely unexplored. Here, soil samples were collected from a long-term land use experiment, including conventional agriculture (CA), tea planting (TP), natural forest (NF), and pine forest (PF). Soil potential N2O-reducing ability, and the abundance and community composition of nosZI and nosZII genes were determined. Both the N2O reducing capacity and the abundance of nosZI and nosZII genes followed the order of CA > TP > NF > PF, and the nosZII abundance was significantly higher than that of nosZI in all samples. Although different land use induced significant shifts in the community structure of both nosZI and nosZII-containing N2O reducers, their response strategies were different. Approximately 37 %–61 % of the total nosZI OTUs were shared by all land use types, and these common OTUs contributed over 90 % of the total relative abundance. In contrast, the proportion of the common nosZII OTUs varied widely from 7 % (CA) to 51 % (PF), and the corresponding relative abundance shifted from 37 % (CA) to 94 % (NF). In conclusion, agricultural practices significantly increased the abundance and capacity of N2O reducers. The nosZI-containing community was relatively stable, while that of nosZII was more sensitive to different land use.
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