Methane animal emission

Johnson, D. E., Ward, B. M., and Ramsay, J. J. (1996). Chapter 15. Livestock methane Current emissions and mitigation potential. In "Nutrient Management of Food Animals to Enhance and Protect the Environment", (E. T. Kornegay, Ed.). CRC Press, Boca Raton, FL. 

In Western Europe around 17% of methane (CH4) emissions come from animal excrement. Organic animal husbandry methods commonly use straw. This is less the case in conventional systems and mostly missing in intensive ones. Liquid manure management shows a great emission potential for methane and ammonia. Incorporating straw in manure diminishes emission risks significantly. 

Tannins represent a class of plant secondary metabolites and are produced by plants in their intermediary metabolism. Tannins are considered to be a promising group of substances to decrease methane (CH ) emission from ruminants by dietary means. However, there is no common agreement whether tannins generally decrease CH formation in vivo or not and to which extent (Beauchemin et al., 2008). Therefore, research on this particular topic is needed to summarize and to quantify the tannin effects on CH production from ruminants and its associated variables. The objective of this study was to estimate the relationship between dietary tannin levels and CH emission from ruminant animals by compiling available literature data of respective experiments using a statistical meta-analysis approach. 

Controlling methane release from wetland, rice paddies and gaseous emissions from animals is more problematic. The release from rice paddies and wet lands is slow, intermittent and takes place over a wide geographic area, and thus very difficult to control. Gaseous emissions from agricultural animals contribute to atmospheric accumulation of methane due to fermentative digestion that produces methane in... 

Boadi, D., Benchaar, C., Chiquette, J., and Masse, D. (2004). Mitigation strategies to reduce enteric methane emissions from dairy cows Update review. Can. J. Anim. Sci. 84,319-335. 

McGinn, S. M., Beauchemin, K. A., Coates, T., and Colombatto, D. (2004). Methane emissions from beef cattle Effects of monensin, sunflower oil, enzymes, yeast, and fumaric acid. /. Anim. Sci. 82, 3346-3356. 

Monteny, G. J., Groenestein, C. M., and Hilhorst, M. A. (2001). Interactions and coupling between emissions of methane and nitrous oxide from animal husbandry. Nutr. Cycl. Agroecosyst. 60,123-132. 

Methane emission from ruminants can be estimated by using the ERUCT technique (Emissions from Ruminants Using a Calibrated Tracer). The tracer can either be isotopic or nonisotopic. Isotopic tracer techniques generally require simple experimental designs and relatively straightforward calculations [31]. Isotopic methods involve the use of (3H-)CH4 or (14C-)CH4 and ruminally cannulated animals. 

Johnson KA, Johnson DE. Methane emissions from cattle. Journal of Animal Science. 1995 73 2483-2492. 

Johnson KA, Westberg HH, Lamb BK, Kincaid RL. The use of sulphur hexafluoride for measuring methane emissions from farm animals. In Proceedings of the 1st International Conference on Greenhouse Gases and Animal Agriculture, Obihiro, Hokkaido, Japan. 2001. pp. 72-81. 

Air pollution in cities can be considered to have three components sources, transport and transformations in the troposphere, and receptors. The sources are processes, devices, or activities that emits airborne substances. When the substances are released, they are transported through the atmosphere, and are transformed into different substances. Air pollutants that are emitted directly to the atmosphere are called primary pollutants. Pollutants that are formed in the atmosphere as a result of transformations are called secondary pollutants. The reactants that undergo the transformation are referred to as precursors. An example of a secondary pollutant is troposphere ozone, O3, and its precursors are nitrogen oxides (NO = NO + NO2) and non-methane hydrocarbons, NMHC. The receptors are the person, animal, plant, material, or urban ecosystems affected by the emissions (Wolff, 1999). 

Schbnwiese (1995) calculates the CH share in the greenhouse effect of about 2.5% and agriculture is believed to account for roughly two-thirds of the total human-generated CH (Watson ef al. 1996). While paddy rice fields, cattle feedlots and the burning of biomass contribute to methane emissions, about 75% of methane on farms is emitted directly from ruminant animals, from digestive processes and excretion (Stolze ef al. 2000, Alfbldi ef al. 2002, Shepherd ef al. 2003). 

The first global CH4 budgets were compiled by Ehhalt (1974) and Ehhalt and Schmidt (1978), who used available published information to estimate emissions of CH4 to the atmosphere. They considered paddy fields, freshwater sources (lakes, swamps, and marshes), upland fields and forests, tundra, the ocean, and enteric fermentation by animals as biogenic sources. Anthropogenic sources included industrial natural gas losses and emission from coal mining, and were considered to be free. Observations of CH4 placed an upper limit on anthropogenic sources. Oxidation by the OH radical, as well as loss to the stratosphere by eddy diffusion and Hadley circulation, were presumed to be methane sinks. In spite of lack of data, this work correctly identified the major atmospheric sources and did... 

Cement production Other industrial processes Human respiration Animal respiration Methane emissions equivalents Natural gas consumption Oil consumption Coal consumption Biomass burning... 

---