Humans Put Amazon to More Danger, Fires

Threats to the Amazon rainforest are more wide-ranging than people realize, revealed a new study in Nature that looks at human activities to which conservation programs have not given adequate attention. The paper warns that disturbances from people may double biodiversity loss, in part by triggering wildfires in the Amazon.

Speaking to BBC News, lead author Jos Barlow of the Lancaster Environment Centre said, "Rainforests don't normally burn. But human activities are making them much more flammable."

Environmental scientists and activists have long been rallying to save the Amazon from deforestation. Many have highlighted the importance of the rainforest as a region of immense biodiversity, nurturing countless species that potentially possess great value to science and medicine. The Brazilian government has aided efforts by designating swathes of the rainforest as protected areas.

Large-scale deforestation is not the only threat to the Amazon, however. Dambuilding and mining activities also contribute, as they can bring about the deterioration of the freshwater ecosystem, noted a 2015 study in Global Change Biology. Now, the current study in Nature examines the combined effects of various small-scale disturbances made by people, including wildfires, hunting, landscape alteration, and selective logging (where only specific tree species are cut down while others are left in place).

The research study focused on biodiversity sampling in areas within the Brazilian state of Pará, a locale that has already gone through considerable deforestation. The sampling included plants, birds, dung beetles, and other organisms-around 2,000 species all told. The results uncovered alarming losses in biodiversity.

By law, Brazilian property owners cannot clear more than 20 percent of primary forest in their Amazon holdings. The researchers did samplings at a number of estates that followed the law in maintaining 80 percent of the forest cover.

Even these areas exhibited significant biodiversity losses ranging from 39 to 54 percent. The researchers concluded that the combined effects of small-scale human disturbances throughout Pará had an impact equivalent to 123,000 square kilometers (around 50,000 square miles) of deforestation.