A recently published article in Nature Geoscience finds that the drivers of tropical deforestation are now likely to be urbanisation and the growth in export agriculture.
DeFries R S, Rudel T, Uriarte M, Hansen M (2010). "Deforestation driven by urban population growth and agricultural trade in the twenty-first century", Nature Geoscience, February 2010.
The paper assesses demographic and economic factors associated with forest loss for 41 countries across the humid tropics. These countries collectively cover 98% of all forest area in the humid tropical forest biome.
For each data both multiple linear regression and regression tree approaches are used to identify relevant factors, the aim being to identify factors most strongly associated with forest loss, rather than to predict forest loss per se. The authors examine ten possible correlates: four demographic factors for 2000-2005 (urban, rural and total annual population growth and per cent of population that is urban), four factors related to agricultural production (net agricultural trade per capita, per cent of agricultural production that is exported, agricultural exports per unit production and per cent forest remaining in biome) and two economic factors (gross domestic product per capita and annual gross domestic product growth).
Both methods show a positive association of forest loss with urban growth and agricultural exports. Although these associations do not prove causality, the positive correlations do suggest that the traditional mode of clearing in frontier landscapes for small-scale production to support subsistence needs or local markets is no longer the dominant driver of deforestation in many places. Rather the higher rates of forest loss for 2000 to 2005 are strongly associated with demands for agricultural products in distant urban and international locations.
You can download the abstract here.
(This is a pay service.)
The Guardian has written an article based on the paper - you can read it here.
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