title: Experimental warming of a mountain tundra increases soil CO2 effluxes and enhances CH4 and N2O uptake at Changbai Mountain, China.
abstract: Climatic warming is expected to particularly alter greenhouse gas (GHG) emissions from soils in cold ecosystems such as tundra. We used 1 m(2) open-top chambers (OTCs) during three growing seasons to examine how warming (+0.8-1.2 °C) affects the fluxes of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) from alpine tundra soils. Results showed that OTC warming increased soil CO2 efflux by 141% in the first growing season and by 45% in the second and third growing season. The mean CH4 flux of the three growing seasons was -27.6 and -16.7 μg CH4-C m(-2)h(-1) in the warmed and control treatment, respectively. Fluxes of N2O switched between net uptake and emission. Warming didn't significantly affect N2O emission during the first and the second growing season, but stimulated N2O uptake in the third growing season. The global warming potential of GHG was clearly dominated by soil CO2 effluxes (>99%) and was increased by the OTC warming. In conclusion, soil temperature is the main controlling factor for soil respiration in this tundra. Climate warming will lead to higher soil CO2 emissions but also to an enhanced CH4 uptake with an overall increase of the global warming potential for tundra.
authors.affiliation: Shanghai Institute of Technology, Shanghai 201418, China.
authors.forename: Yumei
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: Swiss Federal Research Institute WSL, Zuercherstrasse 111, 8903 Birmensdorf, Switzerland.
authors.forename: Frank
authors.initials: F
authors.lastname: Hagedorn
authors.affiliation: Shanghai Institute of Technology, Shanghai 201418, China.
authors.forename: Chunliang
authors.initials: C
authors.lastname: Zhou
authors.affiliation: Shanghai Institute of Technology, Shanghai 201418, China.
authors.forename: Xiaojie
authors.initials: X
authors.lastname: Jiang
authors.affiliation: Changbai Mountain Forest Ecosystem Research Station, Chinese Academy of Sciences, Baihe 133613, China.
authors.forename: Xiuxiu
authors.initials: X
authors.lastname: Wang
authors.affiliation: Swiss Federal Research Institute WSL, Zuercherstrasse 111, 8903 Birmensdorf, Switzerland.|Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China.
authors.forename: Mai-He
authors.initials: MH
authors.lastname: Li