Rights statement: Copyright 2011 by the American Geophysical Union.
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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Ebullition events monitored from northern peatlands using electrical imaging
AU - Kettridge, Nicholas
AU - Binley, Andrew
AU - Green, Sophie M.
AU - Baird, Andy J.
N1 - Copyright 2011 by the American Geophysical Union.
PY - 2011/12
Y1 - 2011/12
N2 - Within northern peatlands, ebullition is potentially an important mechanism for the transport of methane (CH(4)) to the atmosphere. We applied electrical imaging to characterize the buildup and ebullition of biogenic gas bubbles in a spatially explicit manner. Ebullition events were monitored from a range of different peat types, with and without a vascular plant cover, under different meteorological conditions. Weekly changes in bulk electrical conductivity (sigma) were analyzed, during which variations in pore water conductivity had only a small effect on sigma. Bulk ebullition losses from the peat cores were independently measured using Mariotte regulators. The largest ebullition events were found to be spatially diffuse: the gas was released from a large volume of peat. We used a measure of the roughness of the electrical images to characterize the magnitude of gas bubble movement within each peat core. Our results show that small variations in air temperatures of 3 degrees C and variations in peat type between different microhabitats have a statistically significant influence on gas bubble dynamics.
AB - Within northern peatlands, ebullition is potentially an important mechanism for the transport of methane (CH(4)) to the atmosphere. We applied electrical imaging to characterize the buildup and ebullition of biogenic gas bubbles in a spatially explicit manner. Ebullition events were monitored from a range of different peat types, with and without a vascular plant cover, under different meteorological conditions. Weekly changes in bulk electrical conductivity (sigma) were analyzed, during which variations in pore water conductivity had only a small effect on sigma. Bulk ebullition losses from the peat cores were independently measured using Mariotte regulators. The largest ebullition events were found to be spatially diffuse: the gas was released from a large volume of peat. We used a measure of the roughness of the electrical images to characterize the magnitude of gas bubble movement within each peat core. Our results show that small variations in air temperatures of 3 degrees C and variations in peat type between different microhabitats have a statistically significant influence on gas bubble dynamics.
KW - CH4
KW - WATER-CONTENT
KW - PEAT
KW - BIOGENIC GAS-BUBBLES
KW - METHANE EMISSIONS
KW - VASCULAR PLANTS
KW - Ebullition
KW - DYNAMICS
KW - WETLANDS
KW - CARBON TURNOVER
KW - Geophysics
KW - Northern peatlands
KW - resistivity
U2 - 10.1029/2010JG001561
DO - 10.1029/2010JG001561
M3 - Journal article
VL - 116
JO - Journal of Geophysical Research: Biogeosciences
JF - Journal of Geophysical Research: Biogeosciences
SN - 2169-8961
IS - G4
M1 - G04004
ER -