Open AccessTemperature limitation of hydrogen turnover and methanogenesis in anoxic paddy soil
Author(s) -
Conrad Ralf,
Schütz Helmut,
Babbel Monika
Publication year - 1987
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1987.tb02378.x
Subject(s) - methanogenesis , anoxic waters , methane , chemistry , environmental chemistry , incubation , hydrogen , biochemistry , organic chemistry
The shift of incubation temperature in anoxic paddy soil from 30°C to 15°C resulted in a reversible decrease of the methane production rate and of the H 2 steady state partial pressure. Only at 30°C but not at 17°C, total CH 4 production rates were enhanced by the addition of H 2 , acetate, or cellulose compared to the control. Apparent activation energies which were calculated from the temperature dependence of CH 4 production were higher in presence than in absence of excess H 2 . Decrease of temperature caused a decrease of the H 2 turnover rate constant and of the Gibbs free energy of H 2 ‐dependent methanogenesis, and also resulted in a smaller contribution of H 2 to total methanogenesis. However, H 2 ‐dependent methanogenesis was significantly stimulated by excess H 2 and slightly inhibited by acetate at low as well as high temperature. The results show that H 2 ‐producing bacteria were limited by temperature to a greater extent than the methanogens so that the methanogenic microbial community in paddy soil was limited by the supply of H 2 . At low as well as high temperatures, excess H 2 apparently enabled part of the methanogenic community to shift from acetate‐dependent to H 2 ‐dependent CH 4 production. At low temperature, excess H 2 had only this effect, but with increasing temperature, excess H 2 additionally stimulated total methanogenic activity and eventually even growth.