Deforestation in the Amazon

Impending Issues in the Amazon

Deforestation continues to be the dominant land-use trend in Latin America (Fig. 1) (Ramankutty and Foley 1999, Achard et al. 2002), and subsistence agriculture, an important part of many local economies, is one of the major contributors (Chowdhury and Turner 2006, Pan et al. 2007). But, socioeconomic changes related to globalization are promoting a rapid change toward agricultural systems oriented to local, regional, and global markets. The Amazon basin is the region that has lost the largest area to deforestation, and where deforestation has had the greatest impact on biodiversity and biomass loss (Houghton et al. 1991, Laurance 1998, Lambin et al. 2003), but most other biomes have also been and continue to be severely affected by conversion to agriculture and pastures (e.g., Ellenberg 1979, Sader and Joyce 1988, Viña and Cavelier 1999, Galindo-Leal and De Gusmao Camara 2003, Klink and Machado 2005, Viglizzo et al. 2006, Gasparri et al. 2008). Historically, traditional shifting agriculture and cattle ranching, often favored by government subsidies and migration policies, have been the main drivers of deforestation in the Amazon, as well as in other ecosystems in Latin America such as the Andean forests, Central American lowlands, and South American dry forests (Hecht 1993, Kaimowitz 1995, Grau et al. 2008a). Although these driving forces continue to act in many places, export-oriented industrial agriculture has become the main driver of South American deforestation. In Brazil, Bolivia, Paraguay, and Argentina, extensive areas of seasonally dry forest with flat terrain and enough rainfall for rain-fed agriculture are now being deforested for soybean production, which is mainly exported to China and the European Union (Dros 2004). This process affects the species-rich Amazon forests (Fearnside 2001, Killeen et al. 2008) and indirectly favors other forms of degradation beyond the agriculture frontier, such as logging and fire (Nepstad et al. 1999). The expansion of modern agriculture is having its greatest effects on the two most threatened biomes both at global and continental scales (Hoeckstra et al. 2005): tropical and subtropical dry forests (Zak et al. 2004, Grau et al. 2005, Silva et al. 2006) and temperate grasslands and savannas (Paruelo and Oesterheld 2003, Baldi and Paruelo 2008). Although the “soy boom” in Latin America is an important threat to the region’s biodiversity, it has brought large economic benefits to the economy sectors associated with production, transportation, commercialization, and processing of agricultural products and to the local and national governments through taxes. Furthermore, the “soy boom,” partly based on transgenic cultivars, is supplying cheap calories and high-quality protein to help meet the growing demand for food in Southeast Asia, and is thus contributing to increasing nutrition levels in this region.  

Although the efficiency of modern agriculture and the associated lower food costs are positive for consumers, smallhold farmers, particularly those on marginal lands, are frequently unable to compete with large-scale agriculture. This process and the increase in off-farm jobs in the service and industry sectors in the cities stimulate rural–urban migration. The combination of agricultural modernization and rural–urban migration often leads to a shift in the mode of food production and the abandonment of marginal agricultural and grazing land, which can favor ecosystem recovery both as spontaneous processes and by facilitating the implementation of protected areas or conservation policies (Mather and Needle 1998, Mather 2001, Aide and Grau 2004, Grau and Aide 2007, Izquierdo and Grau 2008). Forest transition or more generally, ecological transition (ecosystem recovery occurs also in non-forested biomes), occurs when an economy shifts toward non-agricultural production, agriculture concentrates in the most productive lands, and marginal agriculture is abandoned, favoring the recovery of forests and other natural ecosystems. Although comparatively less important than deforestation and much less perceived by the general public and the scientific community, processes of ecosystem recovery can be observed in many Latin American areas (Fig. 1). Forest expansion or recovery of degraded forests during recent decades has been reported for several Caribbean and Central American areas in association with the strong impact of rural outmigration and economic modernization, including Puerto Rico (Lugo 2002, Grau et al. 2003, Parés Ramos et al. 2008), Dominican Republic (Grau et al. 2008c), Mexico (Klooster 2003, Bray and Klepeis 2005), El Salvador (Hecht et al. 2006), Honduras (Southworth and Tucker 2001), Costa Rica (Kull et al. 2007), and Panama (Wright and Samaniego 2008). In South America, examples of ecosystem recovery include forest expansion in peri-urban ecosystems (Baptista 2008, Grau et al. 2008b), expansion of Andean forests into grasslands (Grau 1985, Kitzberger and Veblen 1999), and land-use disintensification in deserts and semi-arid ecosystems (Moran et al. 1996, Preston et al. 1997, Wiegers et al. 1999, Morales et al. 2005, Jepson 2005, Grau et al. 2008a).

Although agriculture is being abandoned in some marginal areas, in other areas it continues to expand; for example, in regions used for illegal crops. Compared with modern agriculture, which concentrates in fertile and flat soils, illegal crops are often cultivated in marginal areas, mainly because of poor accessibility, which reduces legal controls. The most common of these areas in Latin America are the humid slopes of the Andes, where cultivation of coca and opium are a major source of deforestation and environmental degradation (Cavelier and Etter 1995, Fjdelsa et al. 2005, Bradley and Millington 2008). These areas are also affected by armed conflicts and are outside the legal system of the country, a situation with two contrasting consequences for conservation. On the one hand, social and economic deterioration may lead to outmigration and land abandonment, but on the other hand, conditions for establishment of protected areas and legal enforcement of conservation become very difficult.

Another fact not mentioned in this essay is the possible removal of over 100 uncontacted tribes.

Copyright © 2008 by the author(s). Published here under license by The Resilience Alliance