Returning forests analyzed with the forest identity

Pekka E. Kauppi; Jesse H. Ausubel; Jingyun Fang; Alexander S. Mather; Roger A. Sedjo; Paul E. Waggoner

doi:10.1073/pnas.0608343103

New Research In

Contributed by Paul E. Waggoner, September 27, 2006 (received for review August 9, 2006)

Abstract

Amid widespread reports of deforestation, some nations have nevertheless experienced transitions from deforestation to reforestation. In a causal relationship, the Forest Identity relates the carbon sequestered in forests to the changing variables of national or regional forest area, growing stock density per area, biomass per growing stock volume, and carbon concentration in the biomass. It quantifies the sources of change of a nation's forests. The Identity also logically relates the quantitative impact on forest expanse of shifting timber harvest to regions and plantations where density grows faster. Among 50 nations with extensive forests reported in the Food and Agriculture Organization's comprehensive Global Forest Resources Assessment 2005, no nation where annual per capita gross domestic product exceeded $4,600 had a negative rate of growing stock change. Using the Forest Identity and national data from the Assessment report, a single synoptic chart arrays the 50 nations with coordinates of the rates of change of basic variables, reveals both clusters of nations and outliers, and suggests trends in returning forests and their attributes. The Forest Identity also could serve as a tool for setting forest goals and illuminating how national policies accelerate or retard the forest transitions that are diffusing among nations.

Footnotes

**To whom correspondence should be addressed. E-mail: agwagg{at}comcast.net
Author contributions: P.E.K., J.H.A., and J.F. designed research; P.E.K., J.F., A.S.M., and R.A.S. performed research; J.F. and P.E.W. contributed new reagents/analytic tools; P.E.K., J.H.A., J.F., and P.E.W. analyzed data; and P.E.K., J.H.A., J.F., A.S.M., R.A.S., and P.E.W. wrote the paper.
The authors declare no conflict of interest.
Abbreviations:
FRA2005,
Global Forest Resources Assessment 2005;
FAO,
United Nations Food and Agriculture Organization;
GDP,
gross domestic product;
ha,
hectare.
Freely available online through the PNAS open access option.
© 2006 by The National Academy of Sciences of the USA