Global analysis reveals that changing causes of tropical deforestation are slowly shifting patterns of available tropical forests for biodiversity conservation.
This meta-analysis of 227 case studies undertaken between 1975-2002 on deforestation by Thomas Rudel and colleagues suggest that the growing role of well-capitalized agricultural enterprises in driving deforestation in the tropics could weaken the historically negative relation between population densities and net forest cover.
They identified two periods of change in the historical trajectory of deforestation from these studies, which is particularly pronounced in the lowland forests of Brazil and Indonesia. The first period saw state-enabled, smallholder deforestation (1965–1985), where the relationship between population rise and deforestation was strong — a result of political turmoil, post World War II technological advances combined with rural insurrections in forest rich regions in both Southeast Asia and Latin America. Besides this, a combination of agrarian reforms, land colonization programs, small sized urban labour markets, and large rural-rural migration ensured deforestation in forest frontiers. The second period (post-1985) was the enterprise-driven deforestation phase. Fiscal austerity measures and the debt crisis post-1980s lessened colonization schemes and road building during this period. Highly capitalized enterprises with a small workforce and well-organized associations of farmers represented the private ranchers, timber loggers, and oil palm and soybean plantation farmers, shifting the relationship between population densities and forest loss. Demand from international markets and the debt crisis caused both small farmers and private owners to convert old-growth forests to cattle ranches and oil-palm plantations in the Latin America and Southeast Asia thus intensifying deforestation. Rural population declined and an urban population with increased consumption of agricultural products emerged particularly in Africa. Although African rates of deforestation have remained low, the debt crisis drove smallholders to cater mostly to the international markets. Policy changes or business cycles have also changed the agents of deforestation between years, shifting from smallholders to large-scale enterprises.
Rudel and colleagues inform that an expansion of secondary forests in all three continents is currently occurring because of reforestation in abandoned farmlands or in the form of exotic species plantations, particularly in the upland areas. They suggest that creating new conservation reserves in upland areas is thus a politically palatable strategy, an example being the “Heart of Borneo” network. However, the generality of upland reforestation and viability for conservation is yet to be examined thoroughly. They feel that well-funded and networked conservation organizations along with an environmentally informed public can now bargain with the industrialized agricultural and extractive enterprises to promote lowland stewardship agreements, thus spurring a greater potential for environmental certification to reduce corporate impacts on tropical forests.
Thomas K. Rudel, Ruth DeFries, Gregory P. Asner, and William F. Laurance. 2009. Changing Drivers of Deforestation and New Opportunities for Conservation. Conservation Biology 23(6): 1396-1405.