The rapid expansion of commodity crops, such as soy, coffee, rubber, and oil palm, has been of increasing environmental concern (Meyfroidt et al 2014). Oil palm, in particular, has gained notoriety as the cause of rapid deforestation in Southeast Asia (Carlson et al 2012). International campaigners have called for global boycotts of palm oil, which is ubiquitous in many household products and foodstuffs. But demand for palm oil is rising around the world—global production doubled over just the last decade.
The increasing environmental concern over oil palm production has led to the development of certification schemes, notably the Roundtable for Sustainable Palm Oil. While this is promising, it is difficult to evaluate the effectiveness of such schemes without accurate estimates of forest loss caused by commodity crops such as oil palm. While there have been remarkable breakthroughs in estimating deforestation from space (Hansen et al 2013), such analyses do not specify the source of forest loss. Associating deforestation to the expansion of specific crops is a holy grail.
Furumo and Aide (2017) have conducted one of the few large-scale studies linking deforestation to a particular crop—oil palm. And further, they have performed the first large-scale assessment of oil palm expansion in Latin America and the Caribbean (LAC), whereas most attention to date on oil palm expansion has occurred in Southeast Asia. Their study used their previously developed Land Mapper software to classify oil palm at 250 m spatial resolution using MODIS satellite imagery. After performing accuracy assessment and removing false positives, they then used the most recent Google Earth high-resolution imagery to identify prior land uses.
Furumo and Aide (2017) found that most oil palm expansion in LAC occurred onto grazed land (figure 1), contrary to what has been found in Southeast Asia, despite the LAC countries they studied being 'forested' nations. In particular, they estimated that 79% of oil palm plantations came from 'previously intervened' land. They suggest that cattle ranching and infrastructure development are important precursors for oil palm and other commodity crops in LAC. This finding is consistent with the predictions of bid rent theory, and the hypothesis of Meyfroidt et al (2014) that 'Use of already-cleared lands is favored when commodity crops require access to infrastructure.'
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