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A Comparison of Two Recent Estimates of Disturbance in Tropical Forests

Published online by Cambridge University Press:  24 August 2009

J. M. Melillo
Affiliation:
Associate Scientist, Research Assistant, Assistant Scientist, and Director, respectively, The Ecosystems Center, Marine Biological Laboratory, Woods Hole, Massachusetts 02543, USA.
C. A. Palm
Affiliation:
Associate Scientist, Research Assistant, Assistant Scientist, and Director, respectively, The Ecosystems Center, Marine Biological Laboratory, Woods Hole, Massachusetts 02543, USA.
R. A. Houghton
Affiliation:
Associate Scientist, Research Assistant, Assistant Scientist, and Director, respectively, The Ecosystems Center, Marine Biological Laboratory, Woods Hole, Massachusetts 02543, USA.
G. M. Woodwell
Affiliation:
Associate Scientist, Research Assistant, Assistant Scientist, and Director, respectively, The Ecosystems Center, Marine Biological Laboratory, Woods Hole, Massachusetts 02543, USA.
N. Myers
Affiliation:
Upper Meadow, Old Road, Headington, Oxford, England, UK.

Extract

The two best-documented studies of annual rates of clearing of tropical forests appear to come to very different conclusions; the published FAO/UNEP estimate is 7.4 × 106 ha cleared annually during the late 1970s, and the NAS (National Academy of Sciences) estimate is 22.0 × 106 ha disturbed annually during the same period. Closer examination reveals that when corrections are made for differences in forest types included in the studies, and for differences in definitions of ‘deforestation’ (FAO/UNEP) and ‘conversion’ (NAS), there appears to be general agreement on the rate of deforestation in tropical closed broad-leafed forests: 5.9 × 106 ha (FAO/UNEP) and 7.5 × 106 ha (NAS) per year for the late 1970s. ‘Deforestation’ is defined according to the FAO/UNEP report and is the transformation of closed tropical-broad-leafed forests to either land in the shifting-cultivation cycle or permanently-cleared land.

‘Deforestation’ sensu FAO/UNEP is a more restricted term than the term ‘conversion’ used in the NAS report. ‘Conversion’ includes ‘deforestation’ sensu FAO/UNEP as well as: (1) the temporary clearing of fallow-cycle vegetation from land already in the shifting-cultivation cycle for short-term subsistence agriculture; and (2) the permanent clearing of fallow-cycle vegetation and thus the removal of land from the shifting-cultivation cycle.

Type
Main Papers
Copyright
Copyright © Foundation for Environmental Conservation 1985

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References

REFERENCES

Fearnside, P. M. (1982). Deforestation in the Brazilian Amazon: How fast is it occurring? Interciencia, 7, pp. 82–8.Google Scholar
Hadley, M. & Lanly, J. P. (1983). Tropical forest ecosystems: Identifying differences, seeking solutions. Nature and Resources, 19, pp. 219.Google Scholar
Hecht, S. (1983). Cattle ranching in the Eastern Amazon: Environmental and social implications. Pp. 155–88 in The Dilemma of Amazonian Development (Ed. Moran, E. F.). Westview Press, Boulder, Colorado, USA: xvi + 347 pp., illustr.Google Scholar
Houghton, R. A., Hobbie, J. E., Melillo, J. M., Moore, B., Peterson, B. J., Shaver, G. R. & Woodwell, G. M. (1983). Changes in the carbon content of terrestrial biota and soils between 1860 and 1980: a net release of CO2 to the atmosphere. Ecological Monographs, 53, pp. 235–62.CrossRefGoogle Scholar
Kartawinata, K., Adisoemarto, S., Riswan, S. & Vayda, A. P. (1981). The impact of Man on a tropical forest in Indonesia. Ambio, 10, pp. 115–9.Google Scholar
Lanly, J. P. (1969). Regression de la forêt dense en Côte-d'Ivoire. Bois et Forêts des Tropiques, 127, pp. 4559.Google Scholar
Lanly, J. P. (1982). Tropical forest resources. Forestry Paper No. 30, FAO, Rome, Italy: xi + 106 pp., illustr.Google Scholar
Myers, N. (1980 a). Conversion of Tropical Moist Forests. National Academy of Sciences, Washington, DC, USA: xi + 205 pp.Google Scholar
Myers, N. (1980 b). The present status and future prospects of tropical moist forests. Environmental Conservation, 7 (2), pp. 101–14.CrossRefGoogle Scholar
Ranjitsinh, M. K. (1979). Forest destruction in Asia and the South Pacific. Ambio, 8, pp. 192201.Google Scholar
Salati, E. & Vose, P. B. (1983). Depletion of tropical rainforests. Ambio, 12, pp. 6771.Google Scholar
Woodwell, G. M., Hobbie, J. E., Houghton, R. A., Melillo, J. M., Peterson, B. J., Shaver, G. R., Stone, T. A., Moore, B. & Park, A. B. (1983). Deforestation Measured by Landsat: Steps Toward a Method. Technical Report to the Department of Energy, Washington, DC, USA: ii + 63 pp., illustr.Google Scholar