Effects of warming on N2O fluxes in a boreal peatland of Permafrost region, Northeast China

Qian Cui; Changchun Song; Xianwei Wang; Fuxi Shi; Xueyang Yu; Wenwen Tan

doi:10.1016/j.scitotenv.2017.10.246

Effects of warming on N₂O fluxes in a boreal peatland of Permafrost region, Northeast China

Sci Total Environ. 2018 Mar:616-617:427-434. doi: 10.1016/j.scitotenv.2017.10.246. Epub 2017 Nov 9.

Authors

Qian Cui¹, Changchun Song², Xianwei Wang³, Fuxi Shi³, Xueyang Yu¹, Wenwen Tan³

Affiliations

¹ Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
² Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, PR China. Electronic address: songcc@neigae.ac.cn.
³ Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, PR China.

PMID: 29127796
DOI: 10.1016/j.scitotenv.2017.10.246

Abstract

Climate warming is expected to increasingly influence boreal peatlands and alter their greenhouse gases emissions. However, the effects of warming on N₂O fluxes and the N₂O 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 N₂O 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 1.5m aboveground and soil temperature at 5cm depth by 0.6°C and 2°C, respectively. The average seasonal N₂O fluxes ranged from 6.62 to 9.34μgm^-2h^-1 in the warming plot and ranged from 0.41 to 4.55μgm^-2h^-1 in the control plots. Warming treatment increased N₂O fluxes by 147% and transformed the boreal peatlands from a N₂O sink to a source. The primary driving factors for N₂O fluxes were soil temperature and active layer depth, whereas soil moisture showed a weak correlation with N₂O fluxes. The results indicated that warming promoted N₂O fluxes by increasing soil temperature and active layer depth in a boreal peatland of permafrost zone in Northeast China. Moreover, elevated N₂O fluxes persisted in this region will potentially drive a noncarbon feedback to ongoing climate change.

Keywords: Active layer depth; N(2)O flux; Peatlands; Soil temperature; Warming.