Land clearing

Several studies, based on models, examined the effects of land-use change on the global carbon cycle and conclude that there is a net release of carbon due to land clearing. However, the results and conclusions of these studies are based on assumed sizes of vegetation carbon pools which are inputs to the models. For example, Melillo et al. 24) concluded that boreal and temperate deciduous forests of the northern hemisphere are net sources of atmospheric carbon. Their analysis used values for carbon density derived by Whittaker and Likens 19) from work by Rodin and Bazilevich (27). Rodin and Bazilevich extrapolated results of small, unrelated studies in Europe and the USSR to estimate total biomass of Eurasian boreal and temperate deciduous forests. Their estimates have since been extrapolated to forests worldwide and are used often today. 

Fargione, J., Hill, J., Tilman, D., Polasky, S. and Hawthorne, P. (2008). Land clearing and the biofuel carbon dept. Science Express, published online, 7th February, 2008. 

Hvunan activities have already significantly converted or modified the natural land cover of half of Earth s terrestrial surface. Virtually no region remains untouched by human impacts of some kind. The major land conversions we have accomplished over the past 10,000 years or so include (1) land clearing, mostly through deforestation and... 

DuPont Works, built in 1909 at the village of DuPont, Washington, near Tacoma. It fronts Puget Sound for low-cost shipments to Alaska, Hawaii, the Philippines and some west coast South American ports. The most important outlet of this plant has been, however, to the copper, silver and zinc mines of Idaho and Montana. Expls for quarrying, lumbering, land clearing and seismic prospecting, were also important items... 

The basic difference between the two land clearing methods is that in the "manual" process, fire is the major agent employed to remove vegetation cover and prepare the land for pasture establishment. From an agricultural perspective, burning can be regarded as a fast and economical process to... 

Alegre, J. C. 1985. Effects of land clearing and preparation methods on soil physical and chemical properties and crop performance on an Ultisol in the Amazon Basin. Ph.D. thesis, Raleigh, North Carolina State University. 

Dias, A. C. C. P., and S. Nortcliff. 1985. "Effects of two land clearing methods on the physical properties of an Oxisol in the Brazilian Amazon." Tiopical Agriculture. 62 207-212. 

Luizao, F., P. Matson, R. Livingston, and P. M. Vitousek, 1989. "Nitrous oxide flux following tropical land clearing." Giobal Biogeochemicai Cycles 3 281-285-... 

Seubert, C. E., P. A. Sanchez, and C. Valverde. 1977. "Effects of land clearing methods on soil properties of an ultilsol and crop performance in the Amazon jungle of Pem." Tropical Agriculture. 54 307-321. 

Seubert CJE., Effect of land clearing methods on crop performance and changes in soil properties in an Ultisol of the Amazon Jungle of Peru. MS Thesis, North Carolina State University, Raleigh, N.C., p. 152 ((Quoted in Sanchez, 1976) (1975). 

Land clearing cratering, and general use in rear areas... 

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