Climate change
; Low temperature production
; Permafrost
; Soils
; Temperature
; Thawing
; Wetlands
; Eddy covariance
; Influencing factors
; Methane emissions
; Micrometeorological measurements
; Peat land
; Methane
; methane
; rain
; climate change
; diurnal variation
; eddy covariance
; environmental factor
; global climate
; growing season
; low temperature
; methane
; micrometeorology
; mountain region
; Northern Hemisphere
; peatland
; permafrost
; precipitation (climatology)
; soil temperature
; air temperature
; Article
; atmospheric pressure
; China
; circadian rhythm
; Eddy covariance
; environmental temperature
; growing season
; hysteresis
; microclimate
; observational study
; peatland
; precipitation
; priority journal
; seasonal variation
; soil temperature
; soil water content
; temperature sensitivity
; thawing
; thermal conductivity
; vapor pressure
; vegetation
; water table
; China
Scopus学科分类:
Environmental Science: Water Science and Technology
; Earth and Planetary Sciences: Earth-Surface Processes
; Environmental Science: Environmental Chemistry
英文摘要:
The mid-high latitude permafrost peatlands in the Northern Hemisphere is a major natural source of methane (CH4) to the atmosphere. Ecosystem scale CH4emissions from a typical permafrost peatland in the Great Hing'an Mountains were observed during the growing season of 2014 and 2015 using the open-path eddy covariance method. Relevant environmental factors such as temperature and precipitation were also collected. There was a clear diurnal variation in methane emissions in the second half of each growing season, with significantly higher emission rates in the wet sector of study area. The daily CH4exchange ranged from 1.8�mg CH4m−2�d−1to 40.2�mg CH4m−2�d−1in 2014 and ranged from�−3.9 to 15.0�mg CH4m−2�d−1in 2015. There were no peaks of CH4fluxes during the spring thawing period. However, large peaks of CH4emission were found in the second half of both growing seasons. The CH4emission after Jul 25th accounted for 77.9% of total growing season emission in 2014 and 85.9% in 2015. The total CH4emission during the growing season of 2014 and 2015 was approximately 1.52�g CH4�m−2and 0.71�g CH4�m−2, respectively. CH4fluxes during the growing seasons were significantly correlated with thawing depth (R2�=�0.71, P�<�0.01) and soil temperatures (R2�=�0.75, P�<�0.01) at 40�cm depth. An empirical equation using these two major variables was modified to estimate growing season CH4emissions in permafrost peatlands. Our multiyear observations indicate that the time-lagged volume of precipitation during the growing season is a key factor in interpreting locally inter-annual variations in CH4emissions. Our results suggested that the low temperature in the deep soil layers effectively restricts methane production and emission rates; these conditions may create significant positive feedback under global climate change. � 2017 Elsevier Ltd
Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, China; University of Chinese Academy of Sciences, Beijing, China
Recommended Citation:
Yu X,, Song C,, Sun L,et al. Growing season methane emissions from a permafrost peatland of northeast China: Observations using open-path eddy covariance method[J]. Atmospheric Environment,2017-01-01,153