Savanna, burning

Calculations using the satellite-derived burn area and measured emission ratios of gases for boreal forest fires indicate that the Chinese and Siberian fires of the 1987 contributed 20% of the total CO2 produced by savanna burning, 36% of the total CO produced by savanna burning, and 69% of the total CH4 produced by savanna burning... 

Several observations have shown that hydrogen is affected by pollution sources. The hydrogen molecule is an important product of incomplete combustion in several anthropogenic and natural processes. The production of H2 by industrial combustion and automobiles is estimated to vary from 15 Tg H2/yr (Novelli et al., 1999) to 25 Tg H2/yr (Schmidt, 1974). According to Crutzen et al. (1979) 9 to 21 Tg H2/yr are produced by forest and savanna burning, especially for agricultural purposes in tropical regions. 

Globally, 56% of SO2 emissions in 1990 were from coal, 24% from oil, 15% from industrial processes, and 3% from biomass burning (deforestation, savanna burning, and agricultural waste burning) the remaining 2% were from the use of traditional biomass as a source of residential fuel and from natural gas extraction, distribution, and use (Smith, Pitcher, and Wigley, 2001). 

Tropical forests and savannas are the primary source of C emissions that originate from biomass burning (73, 75). However, temperate forests are also sources of atmospheric carbon. Harmon et al. (77) reported that conversion of primary temperate forests to younger, second-growth forests lead to increases in atmospheric CO2 levels, due to losses in long-term carbon storage within these forests. They ascertained that timber exploitation of 5 million hectares of primaiy forests in the Pacific Northwest of North America during the past century has resulted in the addition of 1,500 Tg of C to the atmosphere. 

Andreae MO, Adas E, Cachier H, Gofer WR III, Harris GW, Helas G, Kopp-mann R, Lacaux JR Ward DE, Trace gas and aerosol emissions from savanna fires, in Levine JS (ed.). Biomass Burning and Global Change, Vol. 1, MIT Press, Gambridge, MA, pp. 278-295, 1996. 

Echalar, F., A. Gaudichet, H. Cachier, and P. Artaxo. 1995. Aerosol emissions by tropical forest and savanna biomass burning characteristic trace elements and fluxes. Geophysical Research Letters 22 3039-3042. 

Pivello-Pompeia, V. R., and L. M. Coutinho 1992. Transfer of macro-nutrients to the atmosphere during experimental burnings in an open cerrado (Brazilian savanna). Journal of Tropical Ecology. 8 487-497. 

Liu X. D., Van Espen P., Adams F., Cafmeyer J., and Maenhaut W. (2000) Biomass burning in southern Africa individual particle characterization of atmospheric aerosols and savanna fire samples. J. Atmos. Chem. 36, 135-155. 

The locations of biomass burning are varied and include tropical savannas (Figure 1), tropical, temperate and boreal forests (Figure 2) and... 

Zepp R. G., Miller W. L., Burke R. A., Parsons D. A. B., and Scholes M. C. (1996) Effects of moisture and burning on soil-atmosphere exchange of trace carbon gases in a southern African savanna. J. Geophys. Res. 101, 23699-23706. 

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