The Amazon forest is continuously losing its ability to accumulate carbon due to the deforestation caused by gold miners in the rainforest, a new study has revealed.
The international study led by the University of Leeds cautioned that the impacts of mining on tropical forests are long-lasting and that active land management and restoration is necessary to recover tropical forests on previously mined lands.
According to the study, gold mining has rapidly increased across the Amazon in recent years, especially along the Guiana Shield, where it is responsible for as much as 90% of total deforestation in the rainforest. The Shield stretches through Guyana, Suriname, French Guiana, Venezuela, small parts of Colombia and northern Brazil, and its forests roughly accumulate 20 billion tonnes of aboveground carbon in its trees.
The study provided detailed field-based information on the regeneration of forests in Guyana after gold mining, and the first ground-based estimate of carbon sink lost as a result of gold mining activities across the Amazon.
The team's findings found that forest recovery rates on abandoned mining pits and tailing ponds are amongst the lowest ever recorded for tropical forests. They estimate that mining-related deforestation results in the annual loss of over two million tons of forest carbon across the Amazon. The lack of forest regrowth observed following mining shows that this lost carbon cannot be recovered through natural regeneration.
The mining-induced depletion of soil nutrients.
Their results suggest that forest recovery is more strongly limited by severe mining-induced depletion of soil nutrients, especially nitrogen, rather than by mercury contamination. The mercury, however, has serious implications on food security, water supply and the local biodiversity.
"This study shows that tropical forests are strongly impacted by mining activities, and have very little capacity to re-establish themselves following mining. Our results clearly show the extraction process has stripped nitrogen from the soil, a critical component to forest recovery, and in many cases directly contributed to the presence of mercury within neighbouring forests and rivers. Active mining sites had on average 250 times more mercury concentrations than abandoned sites,” Dr Michelle Kalamandeen, the leader of the team said.
An Associate Professor in Earth System Dynamics at Leeds, Dr David Galbraith said that "currently approximately 1.3 million square kilometres of the Amazon is under prospecting for mining activities. This research provides support to local and national governance structures to critically approach policy implementation and development for land management, including how and where mining occurs, and more stringent monitoring and action for forest recovery. It shows that carefully planned active restoration projects will be critical in this regard. But responsibility lies beyond remediation efforts to mitigate the damage done. Investors and consumers alike need increased awareness and accountability of the environmental footprints of gold mining."
The Amazon Rainforest and its importance to the world.
The Amazon rainforest provides more than 20% of the world's oxygen and absorbs 2 billion tons of carbon dioxide annually. Therefore, causing harm to the rainforest will have severe consequences for living beings on earth as the rainforest plays a vital role in the prevention of climate change.