Development has affected 7 percent of virgin forests since 2000: Study

On the surface, it’s just a vast expanse of land. But look closer, and the untouched areas of Canada’s boreal forest are a teeming mass of life – one that may hold some life-sustaining answers.

Yet in Canada and worldwide, untouched wilderness is coming under increased pressure, according to research published Friday in the journal Science Advances. The study’s authors, who have been using satellite data to track changes in the world’s intact landscapes for more than a decade, report that 7.2 percent of these areas have been compromised since 2000.

As these landscapes disappear or are sliced up by human activity, the multiplicity of species that inhabit these pristine corners of the earth are threatened. Not only are these species critical to understanding life on earth, but they may also hold hints for sustaining a growing global population. In addition, soils and forests act as a bulwark against the effects of climate change.

“As we lose [pristine areas], we lose something that is bigger than ourselves,” explained forest expert and study co-author Lars Laestadius to the Washington Post.

The authors define an intact forest landscape as a piece of land greater than 500 square kilometers (200 square miles) that has not been touched by human activity, from human-caused wildfires to pipeline construction. These areas can include ecosystems from deserts to wetlands.

What’s driving their decline? With human societies covering an ever-increasing portion of the globe, it’s simply easier to access these once-remote areas, Dr. Laestadius suggested to the Post. NASA’s Earth Observatory indicates that state economic development policies – including building railways and expanding agriculture – have also caused significant deforestation.

When human activity encroaches, it can have a devastating impact on biodiversity. Some species only exist in tiny areas of an ecosystem, notes NASA’s Earth Observatory, meaning that they can be wiped out altogether. And activities such as clear-cutting trees can fundamentally change the types of wildlife that spring up.

With the loss of these species and their habitats comes a corresponding loss in scientific understanding, observed Laestadius.

“As we lose [them], it becomes more difficult for us to understand what is happening in those parts of the world that are already subject to human influence,” he said. “We sort of lose the benchmark of Mother Nature.”

Forests’ biodiversity could hold the clues for all kinds of questions facing life on earth, including feeding a growing population, suggests NASA’s Earth Observatory: “Hidden in the genes of plants, animals, fungi, and bacteria that have not even been discovered yet may be … the key to improving the yield and nutritional quality of foods.”

Old-growth forests may also have an important role to play in combating climate change. All trees and soils store carbon by taking in carbon dioxide. A 2008 study in the journal Nature indicated that old forests were particularly successful as carbon sinks, with those in the Pacific Northwest, Canada, and Russia taking in up to 0.4 gigatons of carbon annually. As these forests are cut down or burned, that stored carbon is released.

At current rates, 19 countries will lose all their intact forests within 60 years, the authors of the new study write – and in four countries, they will be gone within 20 years. With all of the benefits at stake, how can the decline in intact forests be slowed?

Sebastiaan Luyssaert, author of the 2008 study, told Scientific American that more emphasis needs to be placed on protecting existing forests, rather than seeing them as a resource that can be restored.

"Any kind of existing program that gives credit to reforestation could give credits to forest preservation," he suggested. Instead of replanting trees, in other words, use the funds to maintain old forests.

Formal forest protection is another answer. The authors of the Science Advances study found that protected areas were three-and-a-half times less likely to be compromised. But only about a tenth of the remaining untouched areas are protected, they say, highlighting a need for “carbon sequestration and biodiversity conservation efforts that target the most valuable remaining forests.”


Humans have destroyed 7% of Earth’s pristine forest landscapes just since 2000

The world’s natural places are disappearing at a galloping clip, says a new study, released Friday in the journal Science Advances. It suggests that more than 7 percent of Earth’s natural, intact forest landscapes have been lost since 2000 — and these ecosystems may be in danger of disappearing entirely from at least 19 countries in the next 60 years.

These landscapes represent some of “the last portions of the Earth that are not significantly affected by human influence,” said Lars Laestadius, a forest expert, consultant on natural resources policy and co-author of the new study. “As we lose these, we lose something that is bigger than ourselves.” 

The study defines “intact forest landscapes” as areas greater than 500 square kilometers, or 193 square miles, containing a mosaic of forests and other associated ecosystems, such as plains or wetlands. The key is that these areas must be undisturbed by human activities — they can’t be fragmented by roads or deforestation or other industrial operations. Once that happens, the ecosystems cease to be considered “intact.” And as the new study indicates, this is happening more and more frequently around the world.

Using satellite data, the researchers investigated changes to the world’s intact forest landscapes between 2000 and 2013. In 2000, they found that intact forest landscapes covered a total global area of 12.8 million square kilometers, or nearly 5 million square miles. But in the years since, human activities have altered and fragmented many of these areas.

In total, truly intact forest landscapes declined by 7.2 percent. More than half these losses occurred in three countries alone: Russia, Brazil and Canada. In general, though, tropical parts of the world tended to suffer the greatest declines.

The researchers note that these declines don’t necessarily mean that the trees and natural landscapes are disappearing entirely. In many cases, they’re simply being divided up by human activities, fragmented into smaller pieces that no longer qualify as “intact” forest landscapes by the study’s definition.

The rate at which these losses are happening is speeding up, the study suggests. The researchers found that the rate of reductions to intact forest landscapes between 2011 and 2013 was triple the rate between 2001 and 2003. 

The reason for the acceleration is not immediately clear, Laestadius noted, although he said he suspects a big factor is that these ecosystems are simply not as remote as they used to be. As human societies continue to expand, many wilderness areas are just closer to civilization and more accessible than they used to be.

Overall, the researchers found that about 14 percent of the losses were caused by direct alteration of the landscape by activities such as logging and land-clearing. The rest of the losses were caused by fragmentation brought on by road-building and other forms of construction. Timber harvesting, agricultural expansion and human-caused wildfires were the top three specific causes of all losses worldwide, although the greatest disturbances did tend to vary from one region of the world to the next.

This means that the type of action needed to safeguard these landscapes largely varies by country, Laestadius noted. However, the study did indicate that protected areas generally fared better all over the world, suggesting that setting aside nature preserves can be an effective way to reduce forest losses. Worldwide, the researchers found that losses for reasons other than wildfires were 3.4 times higher outside protected areas than inside. 

The speed at which these landscapes are being fragmented and destroyed has produced the alarming possibility that they may disappear altogether in many places by the end of the century. If the current reduction rates continue, the study concludes that at least 19 nations around the world will lose all of their intact forest landscapes in the next 60 years. Four of these — Paraguay, Laos, Cambodia and Equatorial Guinea — may lose them all in the next two decades.

Preventing this from happening is important for a variety of reasons, the researchers note. Intact forest landscapes, by virtue of their size and pristine condition, can provide critical habitat for all kinds of wildlife — conserving them is an important way to safeguard the world’s biodiversity. Many of them are also significant carbon sinks, making them important components of global climate mitigation strategies. Laestadius also noted that the forest landscapes most at risk of destruction are often those with the greatest carbon stores.

“If you’re a logger … of course you’re going to look for the area with the biggest trees, and those will be the areas with the most carbon,” he said. 

But he added that these natural landscapes have value beyond their obvious ecosystem services as well. By virtue of being mainly untouched, they provide an important reference point that shows us how healthy ecosystems function without the influence of human activities. 

“As we lose that it becomes more difficult for us to understand what is happening in those parts of the world that are already subject to human influence,” Laestadius said. “We sort of lose the benchmark of Mother Nature.”

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