Open-Cut Mining is Suffocating the World’s Most Vulnerable Forests

New research has shown that dust from open-cast mining suffocates surrounding forests and inhibits trees’ ability to capture carbon from the atmosphere far more than previously thought. That is, according to researchers from the University of Southampton and the National Institute of Technology in Rourkela, India, who together assessed the impact of mining dust on forests in Eastern India, home to some of the world’s largest open-pit coal mines.

Focusing on Jharsuguda, a major coal mining region in Eastern India, the team studied detailed satellite images to inform its findings. In addition, they collected 300 leaf samples from 30 different sites and found dust deposits containing aluminium, silica, and iron:

“Pollution from open-cast mines creates a layer of dust that settles on the leaves of trees, making them increasingly less productive and less healthy,” according to Jadu Dash, lead author of a new and professor of remote sensing at the University of Southhampton. “We knew this was the case, but we have learned that it is unfortunately worse – and more far spread – than we thought,”

Professor Dash explained that dust affects trees’ complex physiological processes, hindering their ability to capture carbon dioxide and damaging their overall health: “Dust from mines that settles on leaves impacts their function, impeding photosynthesis, light interception, nutrient availability, gas-energy exchange, and plant-pathogen interactions and causing physical damage.”

According to Professor Dash, dust particles obstruct the leaves’ stomata, the tiny openings through which plants exchange gases with the atmosphere. “This reduces the plant’s ability to capture carbon and release oxygen.” Mining dust also impacts trees in a wide geographical area, reaching far beyond the immediate vicinity of the mines – up to 30km away from the mines. The highest concentration of negative impact is along transportation routes to and from the mines.

“We used data from multiple satellite sensors to develop a model to map dust level on leaves,” explained Professor Dash. “This enabled us to understand the regional impact. Using other satellite-based estimates of vegetation productivity, we found that dust accumulation reduces carbon capture and transpiration.”

“Our research should provide a solid foundation to inform future environmental management, as well as demonstrate the need for ongoing research to fully understand and mitigate the negative impact of mining on the delicate surrounding ecosystems.”

Why open-cut mining is a threat to the world’s most vulnerable forests

In October, Wood Central revealed that mining is one of the fastest growing causes of deforestation, with a new report published by the World Resources Institue (WRI) revealing that 1.4 million hectares of forests, an area the size of Montenegro, was lost to the extraction of coal, iron and industrial minerals for the 20 years to 2020.

“Since the turn of the century, mining has increased by 52%,” the WRI said, adding that “in some cases, this extraction has come at the expense of forests, along with burdens to the communities who rely on them.”

“Felling trees also released 36 million tonnes of carbon dioxide equivalent (CO2e) per year into the atmosphere, similar to Finland’s fossil fuel emissions in 2022,” according to the report prepared by Radost Stanimirova, Nancy Harris, Katie Reytar, Ke Wang and Melissa Barbanell.

Using analyzed tree cover loss data from the University of Maryland and a combination of studies on global mining, WRI found that mining had a disproportional impact on some of the world’s most vulnerable forests:

“This includes tropical primary rainforests, some of the world’s most important ecosystems where mining is a growing loss driver, and Indigenous and local community territories, where people depend on forests for their livelihoods.”