| Summary: | Permafrost regions are an important source of greenhouse gases. However, the effects of different permafrost wetland types on greenhouse gas emissions and the driving factors are still unclear in the permafrost region. Here, we selected three typical permafrost wetlands from the Daxing'an Mountains to investigate the effects of permafrost wetland types on greenhouse gas emissions. The cumulative N 2 O, CO 2 , and CH 4 emissions were 84–122, 657,942–1,446,121, and 173–16,924 kg km −2 , respectively. The linear mixed effects model indicated that N 2 O emissions were significantly affected by the NO 3 − -N content, whereas CO 2 emissions were mainly driven by soil temperature, water table level, and NO 3 − -N content. CH 4 emissions were affected by soil temperatue and water table level. Permafrost wetland types significantly affected the average and cumulative N 2 O, CO 2 , and CH 4 emissions. The cumulative N 2 O emissions were highest in the Larix gmelinii - Carex appendiculata ( LC ) wetland and lowest in the Betula fruticosa Pall. ( B ) wetland , driven by NO 3 − -N content. The cumulative CO 2 emissions were highest in the ( B ) wetland and lowest in the L. gmelinii - Ledum palustre var. dilatatum ( LL ) wetland. The cumulative CH 4 emissions from B wetland were significantly higher than those from LL and LC wetlands. The differences in cumulative CO 2 and CH 4 emissions were driven by the water table level. Our findings indicate that NO 3 − -N content affect the spatial-temporal variation of N 2 O emissions, whereas water table level influence the spatial-temporal variation of CO 2 and CH 4 emissions in the permafrost region of the Daxing'an Mountains. Please refer to ReadMe file.
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