According to the Earth Observatory, the single most direct cause of deforestation is conversion of forestry to cropland and pasture. Other causes include urbanization and infrastructure expansion.
The conversion to agricultural land is brought on by other direct factors. Experts say road improvement, while providing access to remote areas, results in some deforestation. Road expansion is followed by legal and illegal logging that creates farmland for new settlers and in turn makes the deforested areas more fire prone. In addition, major scale commercial operations, such as industrial scale cattle ranching in the Amazon in 2006, have been another driving force behind tropical deforestation. Similarly, scientists claim that agricultural tax breaks subsidies and other legal policies that encourage economic development are also underlying causes.
An article on LiveScience notes that effects from tropical deforestation are seen in soil erosion as the World Wildlife Fund states that scientists estimate about 30 percent of the world's fertile land has been lost to deforestation between 1960 to 2013. The resultant soil erosion may lead to contamination of water sources, thereby endangering local populations. Deforestation also causes an increase in greenhouse gas emissions as forest loss contributes 12 to 17 percent of annual emissions, as cited by the World Resources Institute in 2005.