The potent greenhouse gas methane (CH4) is produced in the rumens of ruminant animals from hydrogen produced during microbial degradation of ingested feed. The natural animal-to-animal variation in the amount of CH4 emitted and the heritability of this trait offer a means for reducing CH4 emissions by selecting low-CH4 emitting animals for breeding. We demonstrate that differences in rumen micr...

The Total Carbon Column Observing Network (TCCON) is a global ground-based network of Fourier transform spectrometers that produce precise measurements of column-averaged dry-air mole fractions of atmospheric methane (CH4). Temporal variability in the total column of CH4 due to stratospheric dynamics obscures fluctuations and trends driven by tropospheric transport and local surface fluxes that...

The application of NH4+-based fertilizers is a common practice in rice production. The immediate effect of a late season urea application on the processes involved in CH4 emission from a rice field was investigated on sandy loam located in the valley of River Po at Vercelli, northern Italy, and planted with rice (Oryza sativa, type japonica, variety Koral). Urea, applied at a rate of 50 kg N ha...

From 2012 to 2015, we investigated methane (CH4) distribution, air−sea fluxes, and sediment−water fluxes in an aquaculture bay (Sanggou Bay, China), and estimated the input of CH4 from potential land sources including rivers and groundwater. Surface water CH4 in the bay ranged from 3.0 to 302 nM, while bottom CH4 was usually higher due to sediment release. Water column CH4 in summer and autumn ...

BACKGROUND Effects of elevated atmospheric CO2 concentrations on plant growth and associated C cycling have intensively been studied, but less is known about effects on the fluxes of radiatively active trace gases other than CO2. Net soil-atmosphere CH4 fluxes are determined by the balance of soil microbially-driven methane (CH4) oxidation and methanogenesis, and both might change under elevate...

[1] Much of the 191.8 Pg C in the upper 1 m of Arctic soil of Arctic soil organic mater is, or is at risk of, being released to the atmosphere as CO2 and/or CH4. Global warming will further alter the rate of emission of these gases to the atmosphere. Here we quantify the effect of major environmental variables affected by global climate change on CH4 fluxes in the Alaskan Arctic. Soil temperatu...

An assessment of within field spatial variations in grain yield and methane (CH4) emission was conducted in lowland rice fields of Myanmar. Two successive rice fields (1(st) field and 2(nd) field) were divided into fertilized and non-fertilized parts and CH4 measurements were conducted at the inlet, middle and outlet positions of each field. The results showed that CH4 emissions at non-fertiliz...

Recently reported summertime methane (CH4) emissions (6.7 +/- 13.3 mg CH4/(m2 x hr)) from newly created marshes in the drawdown area of the Three Gorges Reservoir (TGR), China have triggered broad concern in academic circles and among the public. The CH4 emissions from TGR water surfaces and drawdown areas were monitored from 3rd June to 16th October 2010 with floating and static chambers and g...

[1] Methane (CH4) emissions from wetland ecosystems in nothern high latitudes provide a potentially positive feedback to global climate warming. Large uncertainties still remain in estimating wetland CH4 emisions at regional scales. Here we develop a statistical model of CH4 emissions using an artificial neural network (ANN) approach and field observations of CH4 fluxes. Six explanatory variabl...

The natural wetlands of the Tibetan Plateau (TP) are considered to be an important natural source of methane (CH4) to the atmosphere. The long-term variation in CH4 associated with climate change and wetland loss is still largely unknown. From 1950 to 2010, CH4 emissions over the TP were analyzed using a model framework that integrates CH4MODwetland, TOPMODEL, and TEM models. Our simulation rev...