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Fossil Fuel Footprint Stepping on Biodiversity

By Nathalie Butt, Hawthorne Beyer and Leonie Seabrook

The footprint of fossil fuels is encroaching on biodiversity hotspots that are currently undeveloped.

There’s a global biodiversity crisis unravelling before our eyes, and most of the major threats to biodiversity (such as habitat loss and invasive species) are being exacerbated by the growing impact of climate change. Science has convincingly demonstrated the connection between the burning of fossil fuels and climate change. Less well-understood is the impact on our natural world of the actual extraction of these fossil fuels – coal, oil and gas.

The process of extracting fossil fuels, which includes drilling and all forms of mining, has traditionally been seen as a temporary and spatially limited disturbance. In many cases it is assumed that some kind of restoration activity will return the ecosystem to a state close to its pre-disturbance state. Because of this, extraction activities have been considered trivial disruptors of natural systems in comparison with other human activities (such as agriculture). Indeed, in many countries extraction areas are considered “borrowed” rather than “consumed”.

The assumption of a relatively small disturbance footprint (e.g. less than 0.05% of the land surface of Australia is disturbed by mining) has meant that it was previously easy to dismiss the environmental impacts of extraction as unimportant at larger scales. But should it be dismissed? In reality, ecosystem disturbance and degradation, as a direct or indirect result of extraction, has an increasingly large footprint.

In order to meet demand driven by economic growth, fossil fuel consumption is projected to increase dramatically by 2035, with oil demand increasing by more than 30% and natural gas and coal demand increasing by around 50%. As the most easily accessed reserves are depleted, attention is shifting to new areas and methods, such as coal seam gas and shale oil extracted by fracking. This threatens regions that are currently undeveloped and often highly biodiverse.

The direct impacts of fossil fuel extraction on biodiversity include local-scale habitat degradation, species loss, disturbance, fragmentation and edge effects, all of which can compromise ecosystem function at larger scales. The indirect effects of extraction, however, can have even more profound, large-scale impacts on biodiversity. The infrastructure required to support extraction – roads, airports, power lines and towns – facilitates further human development and a resulting cascade of impacts including land clearing, species invasions and the illegal harvesting of wildlife. The third category of impact is the consequences of disasters such as catastrophic oil spills.

Given the distribution of known fossil fuel reserves and biodiversity, which areas raise particular concern? We mapped the spatial overlap between areas of high marine and terrestrial biodiversity and reserves of fossil fuel. We also compared where high numbers of threatened species were in relation to reserves of fossil fuels. Based on this analysis, we identified two key areas most at risk from future fossil fuel development: northern South America (the Amazon Basin) and the western Pacific Ocean (the Coral Triangle).

The Amazon Basin, which covers nine countries in South America, contains 10% of the world’s biodiversity, more than 50% of it is tropical forest. The Coral Triangle in South-East Asia is the most biodiverse marine area of the world, containing two-thirds of the world’s coral species and one-third of the world’s species of fish.

Our analysis revealed broad classes of threat level. Eco­regions such as North Burma, Senegal and Ecuador have medium-to-high species richness but are in areas of small petroleum reserves, so we would expect the pressure on biodiversity from fossil fuel extraction to be low. Regions with large petroleum deposits but low species richness are expected to experience habitat degradation and associated processes, but the net impact on biodiversity will be relatively small.

Many of the countries with both high biodiversity and expanding fossil fuel extraction suffer from poor regulation and enforcement. They also lack the ability to respond effectively to environmental disasters that are too frequently connected to the extraction of fossil fuels. Such regions may also be too remote to attract media coverage, and thus environmental damage caused in these areas may remain undetected and unaddressed.

It is essential that fossil fuel extraction in these regions takes place according to best practices, including rigorous environmental monitoring to ensure that damage is minimised. International environmental organisations could fulfil an essential role by ensuring that fossil fuel extraction takes place according to best practice and ideally avoids areas of high biodiversity.

It is crucial that trade-offs between biodiversity conservation and development are properly assessed to ensure that threatened or endemic species are not lost.

Nathalie Butt, Hawthorne Beyer and Leonie Seabrook are members of the Environmental Decisions Group and are based at the University of Queensland.