Quantifying in-house emissions of methane (CH4) from liquid manure (slurry) is difficult due to high background emissions from enteric processes, yet of great importance for correct estimation of CH4 emissions from manure management and effects of treatment technologies such as anaerobic digestion. In this study CH4 production rates were determined in 20 pig slurry and 11 cattle slurry samples ...

The objective of this study was to determine the genetic parameters of methane (CH4) emissions and their genetic correlations with key production traits. The trial measured the CH4 emissions, at 5-min intervals, from 1225 sheep placed in respiration chambers for 2 days, with repeat measurements 2 weeks later for another 2 days. They were fed in the chambers, based on live weight, a pelleted luc...

Intensification of livestock production makes correct estimation of methanogenesis in liquid manure increasingly important for inventories of CH4 emissions. Such inventories currently rely on fixed methane conversion factors as knowledge gaps remain with respect to detailed temperature responses of CH4 emissions from liquid manure. Here, we describe the temperature response of CH4 production in...

Methane is the second most important long-lived greenhouse gas and plays a central role in the chemistry of the Earth’s atmosphere. Nonetheless there are significant uncertainties in its source budget. Analysis of the isotopic composition of atmospheric methane, including the doubly substituted species CH3D, offers new insight into the methane budget as the sources and sinks have distinct isoto...

This study presents experimental measurements of the biochemical methane production for whole and lipid extracted Nannochloropsis salina. Results show whole microalgae produced 430 cm(3)-CH4 g-volatile solids(-1) (g-VS) (σ=60), 3 times more methane than was produced by the LEA, 140 cm(3)-CH4 g-VS(-1) (σ=30). Results illustrate current anaerobic modeling efforts in microalgae to biofuel assessme...

Sensitive photoacoustic detection of methane (CH4), hydrogen chloride (HCl) and water vapour (H2O) in the near-infrared range using semiconductor DFB lasers is reported. A detection limit of 0.17 ppm of CH4, 0.2 ppm of HCl and 0.024 ppm of H2O (signal-to-noise ratio = 3) is reached using a properly designed photoacoustic cell operating in its first longitudinal mode.

Acid rain sulphate (SO4 2 ) deposition is a known suppressant of methane (CH4) emission from wetlands. However, the hypothesised mechanism responsible for this important biogeochemical interaction, competitive exclusion of methanogens by dissimilatory SO4 2 reducing bacteria (SRB), lacks supporting evidence. Here, we present data from an acid rain simulation experiment in the Moidach More peat ...

In contrast to other oligotrophic water bodies the Gulf of Mexico (GOM) hosts an abundance of hydrocarbon seeps, which likely influences the microbial assemblages it hosts particularly regarding the availability of labile carbon in the aphotic GOM. The aphotic zone receives direct injection of seep methane (CH4), but CH4 from an unknown source has been reported at supersaturated concentrations ...

[1] As natural sources of methane (CH4), peatlands play an important role in the global carbon cycle. Climate models predict that evapotranspiration will increase under a 2 CO2 scenario due to increased temperatures leading to lowered water tables at many northern latitudes. Given that the position of the water table within a peatland can have a large effect on CH4 emissions, climate change may...

The methane potential of activated sludge from six Swedish pulp and paper mills was evaluated. The methane production potential of sludge samples ranged from 100-200 NmL CH4 g(-1) volatile solids (VS) and for four of the six sludge samples the potential exceeded 170 NmL CH4 g(-1) VS. The effects of sludge age and dewatering on the methane production potential were evaluated. The effects of enzy...