Premium
Trophic status impacts both the magnitude and stable carbon isotope composition of methane flux from peatlands
Author(s) -
Hornibrook Edward R. C.,
Bowes Helen L.
Publication year - 2007
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/2007gl031231
Subject(s) - bog , peat , methanogenesis , flux (metallurgy) , methane , stable isotope ratio , environmental science , environmental chemistry , isotopes of carbon , trophic level , atmosphere (unit) , carbon fibers , sphagnum , atmospheric sciences , ecology , chemistry , geology , total organic carbon , biology , physics , materials science , organic chemistry , quantum mechanics , composite number , composite material , thermodynamics
The influence of trophic status on CH 4 production, emission and stable carbon isotope composition was investigated in two ombrogenous and two minerotrophic peatlands situated in Wales, UK. Methane production and emission rates were highest in the minerotrophic peatlands and CH 4 in both pore water and emissions to the atmosphere were notably 13 C‐enriched compared to the ombrogenous bogs. Highly negative δ 13 C values (−95 to −82‰) for CH 4 flux from the acidic rainfed peatlands likely resulted from a combination of CO 2 /H 2 methanogenesis and isotope effects associated with diffusion of CH 4 through aerenchymatous tissue of vascular flora. The δ 13 C values presently attributed to CH 4 flux from northern wetlands in isotope‐weighted mass balance budgets of the CH 4 cycle may be too positive. Methane flux from northern bogs and fens should be assigned different δ 13 C values because CH 4 is notably more 13 C‐depleted in the former, albeit emission strength typically is weaker.