Between 1993 and 2007 (the year of the latest census), the population of the Peruvian Amazon went up over 20 percent, to some 7.5 million. But urban areas grew much faster; so many people moved from the countryside to the cities, rural populations of some provinces saw declines of up to 60 percent. This is true around the frontier city of Pucallpanow Peru's fourth-largest municipality, and a trading hub for the western Amazon. Much of the Brazilian Amazon is undergoing a similar transformation. Rural populations in almost all nine nations comprising the Amazon basin, which also include Venezuela, Colombia and Bolivia, are projected also to decline, even if cities grow.
Ever denser spiderwebs of roads are spreading from these cities, making previously inaccessible places reachable for logging, farming and other activities. On top of this, the Amazon suffered massive droughts in 2005 and 2010events previously thought to take place only once every 100 years. In lands already made more flammable by logging of humid old-growth rainforests, this led in 2005 to fires that burned some 800,000 acres, by conservative estimates, in the Brazilian state of Acre and around Pucallpa alone. A 2011 study by members of the Columbia team indicates that the droughts are connected to fluctuations in temperature over the faraway Atlantic Ocean; some models project they will get worse as global climate warms.
To assess the prevalence and causes of uncontrolled blazes, the researchers combined region-wide climate data, remote-sensing images of land use and fires, and field interviews with farmers around Pucallpaoften conducted amid fires that were still burning. (See slideshow and videos of the team's fieldwork) Not surprisingly, they found that dry condi
|Contact: Kevin Krajick|
The Earth Institute at Columbia University