Carbon cycle fires

Like all matter, carbon can neither be created nor destroyed it can just be moved from one place to another. The carbon cycle depicts the various places where carbon can be found. Carbon occurs in the atmosphere, in the ocean, in plants and animals, and in fossil fuels. Carbon can be moved from the atmosphere into either producers (through the process of photosynthesis) or the ocean (through the process of diffusion). Some producers will become fossil fuels, and some will be eaten by either consumers or decomposers. The carbon is returned to the atmosphere when consumers respire, when fossil fuels are burned, and when plants are burned in a fire. The amount of carbon in the atmosphere can be changed by increasing or decreasing rates of photosynthesis, use of fossil fuels, and number of fires. 

Forest and other fires which contribute large-scale and long-term changes to characteristics of the carbon cycle (of th eglobal pure primary production of 57 GtCyr 1, approximately 5%—10% is emitted to the atmosphere due to wood burning). 

Kasischke E. S. and Stocks B. J. (eds.) (2000) Fire, Climate Change, and Carbon Cycling in the Boreal Forest. Springer Ecological Studies, New York, vol. 138, 461pp. 

Levine J. S. and Cofer W. R. (2000) Boreal forest fire emissions and the chemistry of the atmosphere. In Fire, Climate Change and Carbon Cycling in the North American Boreal Forests, Ecological Studies Series (eds. E. S. Kasischke and B. J. Stocks). Springer, New York. 

Flame retardants were not generally effective. The combustion of asphalt occurs in a stable diffusion flame above the material surface. Heat from the flame is transmitted back to the asphalt causing vaporization. Vapors enter the flame, react exothermally, and continue the cycle. Fire retardants must therefore inhibit vapor phase combustion. Retardants tested included ethyl iodide, bromotrichloromethane, methyltri-chlorosilane, all of which increased the flash point appreciably, and chloroform, carbon tetrachloride, and potassium bicarbonate, all of which helped only at higher percent sludge formulations. 

The turnover and stability of SOM depends mainly on environmental and biological parameters. Either biomass production or decomposition rates are affected. Additionally, soil matrix and litter quality and fire frec uencies stabilize carbon in soils. From the presented results it is obvious that eco.systems have different mechanisms for stabilizing SOM, which lead to different chemistries of the stable compounds. For a better understanding of SOM in the terrestrial carbon cycle and to identify the missing carbon sink, some major points have to be considered ... 

J.-R, Shea, R., and Crutzen, P. J. (1996). Black carbon formation by savanna fires Measurements and implications for the global carbon cycle. /. Geophys. Res. 101, 23,651-23,665. 

These three fluxes are the direct anthropogenic perturbations to the carbon cycle and are assumed to be negligibly small in preindustrial times. This is an excellent assumption for Ff and Fr, but it also presumes that natural forest fires (F ) were responsible for small emissions of C02. 

Bio-briquettes (biomass briquettes) are a biofuel substitute to coal and charcoal. They are used to heat industrial boilers in order to produce electricity from steam. The most common use of biobriquettes is in the developing world, where energy sources are not as widely available. There has been a move to the use of briquettes in the developed world throngh the nse of co-firing, when the briquettes are combined with coal in order to create the heat supplied to the boiler. This reduces carbon dioxide emissions by partially replacing coal used in power plants with materials that are already contained in the carbon cycle. 

What effect would a forest fire have on the carbon cycle Explain. 

Chiesa and Con.sonni [1,3] have made detailed studies of how a CO2 tax would affect the economic viability of several of these cycles when a tax and CO2 removal are introduced. Fig. 8.27 shows their results on the cost of electricity for natural gas-fired plants plotted against the level of a carbon tax (in c/kg CO2 produced), for two of the novel cycles studied here, in comparison with an existing CCGT plant with natural gas firing. 

Kuhlbusch, T. A. J., and P. J. Crutzen, Toward a Global Estimate of Black Carbon in Residues of Vegetation Fires Representing a Sink of Atmospheric C02 and a Source of 02, Global Bio-geochem. Cycl., 9, 491-501 (1995). 

Hammes, K., Schmidt, M. W. I., Smernik, R. J., et al. (2007). Comparison of quantification methods to measure fire-derived (black/elemental) carbon in soils and sediments using reference materials from soil, water, sediment and the atmosphere. Global Biogeochem. Cycl. 21, doi 10.1029/2006GB002914. 

Kuhlbusch,T. A. I, and Crutzen,P. J. (1995).Toward aglobal estimate of black carbon in residues of vegetation fires representing a sink of atmospheric C02 and a source of 02. Global Biogeochem. Cycl. 9,491-501. 

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