Resumen
Climate warming and vegetation composition change are expected to influence greenhouse gas emissions from boreal peatlands. However, the interactive effects of warming and different vegetation compositions on N2O dynamics are poorly known, although N2O is a very potent greenhouse gas. In this study, manipulated warming and vegetation composition change were conducted in a boreal peatland to investigate the effects on N2O fluxes during the growing seasons in 2015 and 2016. We did not find a significant effect of warming treatment and combination treatments of warming and vegetation composition change on N2O fluxes. However, sedge removal treatment significantly increased N2O emissions by three-fold. Compared with the treatment of shrub and sedge removal, the combined treatment of warming and shrub and sedge removal significantly increased N2O consumption by five-fold. Similar to N2O fluxes, the cumulative N2O flux increased by ~3.5 times under sedge removal treatment, but this effect was not significant. In addition, the results showed that total soil nitrogen was the main control for N2O fluxes under combinative treatments of warming and sedge/shrub removal, while soil temperature and dissolved organic carbon were the main controls for N2O release under warming combined with the removal of all vascular plants. Our results indicate that boreal peatlands have a negligible effect on N2O fluxes in the short-term under climate change, and environmental controls on N2O fluxes become increasingly important under the condition of warming and vegetation composition change.