Greater demand for gold in the face of global financial uncertainty and for products such as jewellery has fuelled more mining for the precious metal, with production up from around 2,445 tonnes in 2000 to 2,770 tonnes in 2013, researchers said.
The high price of gold has led to mining in more remote areas where it had not previously been profitable, including underneath tropical forests, according to research published in the journal Environmental Research Letters.
Around 1,680 square kilometres (650 square miles) of tropical forest in South America – an area larger than Greater London – was lost between 2000 and 2013 as a result of gold mining, the study found.
Most of the deforestation for mining occurred after 2007, when gold demand increased following the financial crisis as investors sought a safe haven for their money.
The researchers assessed the impact of gold mining on forests in Colombia, Venezuela, Guyana, Suriname, French Guiana, Brazil, Ecuador, Peru and Bolivia, by comparing locations of newly developed mines since 2000 and changes in forest cover.
More than 90 per cent of the deforestation for gold mining occurred in just four hotspots, the experts from the University of Puerto Rico found.
Although there was little deforestation inside areas protected for wildlife, around a third of the forest loss occurred within a few miles (10km) of conservation areas, putting them at risk from the impacts of gold mining.
Gold mining involves cutting down trees and vegetation for pits, roads and settlements, and leads to air, soil and water pollution from the use of arsenic, cyanide and mercury in the precious metal’s production.
The deforestation causes loss of wildlife, changes to rainfall patterns and increased carbon dioxide emissions.
Destruction of tropical forests has mainly been down to the expansion of agricultural land and cattle ranching, timber extraction and the spread of towns and cities.
But the researchers said deforestation caused by gold mining had become a “major threat” to some of the most remote and better-conserved old-growth forests in South America.
Lead author Nora Alvarez-Berrios said: “Although the loss of forest due to mining is smaller in extent compared to deforestation caused by other land uses, such as agriculture or grazing areas, deforestation due to mining is occurring in some of the most biologically diverse regions in the tropics. For example, in the Madre de Dios region in Peru, one hectare of forest can hold up to 300 species of trees.
“To decrease the amount of deforestation that is occurring as a result of gold mining in the tropical forests, it is important that awareness is raised among gold consumers to understand the environmental and social impacts of buying gold jewellery or investing in gold.
“It is important to also encourage more responsible ways of extracting gold by helping miners to extract in a more efficient way to reduce deeper encroachment into the forests.”