Effects of warming on N 2 O fluxes in a boreal peatland of Permafrost region, Northeast China

Abstract Climate warming is expected to increasingly influence boreal peatlands and alter their greenhouse gases emissions. However, the effects of warming on N 2 O fluxes and the N 2 O budgets were ignored in boreal peatlands. Therefore, in a boreal peatland of permafrost zone in Northeast China, a simulated warming experiment was conducted to investigate the effects of warming on N 2 O fluxes in Betula . Fruticosa community ( B . Fruticosa ) and Ledum . palustre community ( L . palustre ) during the growing seasons from 2013 to 2015. Results showed that warming treatment increased air temperature at 1.5 m aboveground and soil temperature at 5 cm depth by 0.6 °C and 2 °C, respectively. The average seasonal N 2 O fluxes ranged from 6.62 to 9.34 μg m − 2  h − 1 in the warming plot and ranged from 0.41 to 4.55 μg m − 2  h − 1 in the control plots. Warming treatment increased N 2 O fluxes by 147% and transformed the boreal peatlands from a N 2 O sink to a source. The primary driving factors for N 2 O fluxes were soil temperature and active layer depth, whereas soil moisture showed a weak correlation with N 2 O fluxes. The results indicated that warming promoted N 2 O fluxes by increasing soil temperature and active layer depth in a boreal peatland of permafrost zone in Northeast China. Moreover, elevated N 2 O fluxes persisted in this region will potentially drive a noncarbon feedback to ongoing climate change.