Atmospheric pressure
; Carbon dioxide
; Data fusion
; Freezing
; Greenhouse gases
; Land use
; Methane
; Thawing
; Wetlands
; Biogeochemical modeling
; Chemical transport models
; China
; Interannual variability
; Land-use change
; Natural wetland
; Scientific community
; Temperature regimes
; Climate change
; methane
; water
; anthropogenic effect
; carbon dioxide
; climate change
; climate effect
; diurnal variation
; eddy covariance
; land use change
; methane
; research work
; seasonal variation
; temperature gradient
; uncertainty analysis
; wetland
; air pressure
; China
; circadian rhythm
; climate change
; dynamics
; Eddy covariance
; freezing
; greenhouse gas
; priority journal
; Review
; seasonal variation
; temperature
; thawing
; uncertainty
; warming
; wetland
; 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:
Natural wetlands represent the largest single source of methane (CH4), a potent greenhouse gas. China is home to the world's fourth largest wetland area, and it is facing intense climate- and human-related impacts. The scientific community in China has invested considerable effort into investigating wetland CH4release and its dynamics. Static chamber and eddy covariance observations have verified the temperature, water regime and air pressure as factors that regulate the diurnal and seasonal variation of CH4release. Non-growing seasons, especially freezing–thawing cycles, play a role in CH4release. However, a knowledge gap still exists with respect to the inter-annual variability of CH4release. Observations also suggest that water and temperature regimes control the micro- and macro-scale spatial pattern of CH4release, respectively. Recent bookkeeping surveys, biogeochemical model simulations, and chemical transport model inversions, have narrowed the uncertainty range of national CH4release to 2.46–3.20, 2.77–4.95 and 2.38–4.91�Tg CH4yr−1, respectively. Wetland loss (especially cropland conversion in Northeast China), despite climate changes, decreased CH4release by 45.2%–52.2% from the 1950s–2000s, and by 13.2%–15.4% from the 1980s–2000s. However, future warmer temperatures and rising CO2are predicted to strengthen national CH4release by 32% (RCP2.6), 55% (RCP4.5) and 91% (RCP8.5) by the 2080s, albeit without the variation in wetland extent having been considered. Furthermore, future research should emphasize the mechanisms involved in CH4release during freezing–thawing cycles and interannual variability. Model–data fusion of eddy covariance and manipulative experiments, especially warming and CO2enrichment, would benefit estimations and projections of CH4release. � 2017 Elsevier Ltd
Key Laboratory of Mountain Surface Processes and Ecological Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu, China
Recommended Citation:
Wei D,, Wang X. Uncertainty and dynamics of natural wetland CH4 release in China: Research status and priorities[J]. Atmospheric Environment,2017-01-01,154