Scientists warn only 'simplified', degraded tropical forest may remain by end of century

August 24, 2015
Scientists warn only ‘simplified’, degraded tropical forest may remain by end of century
A logged canopy emergent in Brazilian Amazonia. If protected from further impacts, selectively logged forest retains most biodiversity and much carbon. Credit: David Edwards

A new and more dangerous phase of impacts on the world's remaining tropical forests is emerging, threatening to simplify the world's most diverse ecosystem including mass species loss, according to new UCL-led research published today in Science.

The impact of humans on these areas has been increasing for millennia and today more than three-quarters of the world's remaining have been degraded by human actions.

The scientists identified three prior phases of expanding impacts, the first when hunter-gatherers moved into tropical forests and the second following the emergence of , some 6,000 years ago. Under both, the overall health of tropical forests was maintained.

Today, we live in the third phase, marked by much greater impacts, with distant decision-makers directing how land is used, including permanent intensive agriculture, often for soybeans or palm oil, frontier industrial logging for timber export, cross-continental species invasions, and early impacts. The scientists term this phase the era of 'Global Integration', affecting even the most remote areas.

Lead author, tropical forest expert Dr Simon Lewis (UCL Geography and University of Leeds) said: "Earth has lost 100 million hectares of tropical forest over the last 30 years, mostly to agricultural developments. Few people think about how intertwined with tropical forests we all are. Many foodstuffs include palm oil which comes from once pristine Asian tropical forest, while remaining intact forests are buffering the rate of climate change by absorbing about a billion tonnes of carbon each year."

Current trends look set to intensify without major policy changes, as global food demand is projected to double, over 25 million kilometres of road are predicted to be built by 2050, and climate change intensifies, ushering in a new phase of human dominance of tropical forests.

Dr Lewis added: "I fear a global simplification of the world's most complex forests. Deforestation, logging and road building all create fragmented patches of forest. However, as the climate rapidly changes the plants and animals living in the rainforest will need to move to continue to live within their ecological tolerances. How will they move? This is a recipe for the mass extinction of tropical forest species this century.

"What is needed are unbroken areas of forest that link today's core tropical regions with forest areas about 4 degrees cooler, so as temperatures rise and rainfall patterns change species have a better chance of surviving rapid 21st century climate change. We need to bring conservation in line with the reality of climate change."

The authors note that while deforestation and degradation continue, more optimistically, logged forest retains many environmental benefits, and marginal agricultural lands are being abandoned, which can return back to forest.

Dr David Edwards (University of Sheffield), co-author of the study, said: "Much biodiversity still remains in selectively logged forests, and can recover in secondary forests that grow on abandoned farmland. There is abundant potential to incorporate these forests into global plans to make tropical biodiversity climate change ready.

"Despite their value for biodiversity, logged-over and old secondary forests are frequently threatened by conversion to species-poor agricultural plantations. We urgently need to protect these human-impacted forests, especially in regions such as Southeast Asia where almost nowhere is left undegraded."

A suite of policy measures can help tropical forests survive, including giving forest dwellers formal collective legal rights over their land, which previous studies have shown is one of the best ways of preserving forests. A study of 292 protected areas in Amazonia showed that indigenous reserves were the most effective at avoiding deforestation in high pressure areas.

Most of the financial benefits of logging and plantation agriculture, such as palm oil, flow out of the forests. Ensuring local people have collective long-term rights over their lands would mean that benefits flowing from forest lands accrue to local people. This can provide the beginnings of programs of 'development without destruction', tackling poverty while maintaining forests. This, the authors argue, provides human rights and conservation win-wins.

Dr Lewis added: "With long-term certainty of tenure people can plan, maintaining forests while investing in improving agricultural productivity without expanding into forested lands. Forest dwellers won't be perfect managers of forests, but they won't look for a quick profit and then move on, as big businesses often do.

"This is a pivotal year for the global environment. There are some good signs for the world's tropical forests, with the UN New York Declaration on Forests agreeing to not only halt deforestation, but also restore 150 million hectares of forest. However, there are ominous signs too, with the industry having driven the world's highest deforestation rates in South East Asia now gearing up to repeat this process across Africa.

"The Paris climate change talks in December are doubly important for forests and forest communities. The levels of emission cuts will be a critical factor in determining how many tropical forest plants and animals go extinct over the coming decades and centuries. The agreements on reducing deforestation, including durable finance, will be pivotal. The final test will be whether some funds for adaptation will include land-use planning to retain connectivity as the climate rapidly changes."

Explore further: Climate change just one of many risks to trees in the tropical Andes

More information: "Increasing human dominance of tropical forests." Science 21 August 2015: DOI: 10.1126/science.aaa9932

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verkle
Aug 24, 2015
This comment has been removed by a moderator.
gkam
2.8 / 5 (9) Aug 24, 2015
Perhaps that is because you do not fully understand the issues. They are complex, but we live supported by a web of life, which cleans our water, makes our Oxygen and provides us with food. We need all the threads to hold it together, because they all depend on each other and are interlinked.

Please go to school before you folk make the decisions which kill us.
TheGhostofOtto1923
3.9 / 5 (7) Aug 24, 2015
How can you blame countries located in the tropics that need to expand farmland, areas for towns, roads, etc. because they want to reduce their tropical forest areas? Seems inevitable to me. Unfortunate, yes, but we have to learn to deal with it
These areas are inhabited by people in the thrall of organized religions which force overgrowth.

And youre again right - this makes the destruction of ecosystems inevitable.

The only way to prevent this is to end the religions which cause it.

Including yours.
jeffensley
1 / 5 (3) Aug 24, 2015
How can you blame countries located in the tropics that need to expand farmland, areas for towns, roads, etc. because they want to reduce their tropical forest areas? Seems inevitable to me. Unfortunate, yes, but we have to learn to deal with it.



In principle I agree. It's nothing if not arrogant for the Western World, who has already gone through this process for their own economic gain, to say that other countries should not be allowed to do the same. But if we want to prevent deforestation, I believe it should be done through educated consumers and not through "force" via world governing organizations.
TheGhostofOtto1923
3.7 / 5 (3) Aug 24, 2015
Rape of the environment needs to be stopped by force. The people who are doing it are already breaking laws.

Poachers need to be hunted. Illegal loggers need to be arrested and jailed. Squatters need to be driven off.

They are free to try to swim to greece or force their way across the macedonian border or smuggle themselves into the US if they want, but they may well die.

NONE of this would be happening if the people were without religion and could learn the value of living within their means. God teaches the faithful that he will provide for as many children as they can bear.

We are watching them drown by the 1000s trying to cross the mediterranean.
rgw
not rated yet Aug 24, 2015
"God teaches the faithful that he will provide for as many children as they can bear.
We are watching them drown by the 1000s trying to cross the mediterranean."

The good news is that not a single 'bear' has drowned trying to cross the same body of water.
* Just hunting poachers won't work.They have to be shot or beaten/ stabbed so as to not increase the mass shooting statistics.
* Just Jailing loggers will create an entire raft of other problems.
* Fortunately the 'squatters' can all be quartered at Otto's house.
leetennant
5 / 5 (6) Aug 24, 2015
These forests aren't being cut down for local prosperity and development. They're being cut down by large multinationals for the developed world to use. The locals get nothing but dispossesion, wage slavery, exploitation and the loss of their natural resources. Not to mention the flow-on effect for climate change.
Shootist
1 / 5 (5) Aug 24, 2015
2 million years ago the Amazon didn't exist, it was grassland (plains, steppe, pampas). Someday the Amazon will be gone again.

The Climate Changes due to reasons YOU DO NOT UNDERSTAND - Freeman Dyson

leetennant? The locals get jobs and feed their family, you hammerhead.
Captain Stumpy
5 / 5 (4) Aug 25, 2015
The Climate Changes due to reasons YOU DO NOT UNDERSTAND - Freeman Dyson
as per Pink's request, and completely relevant to the post of shootist, who's IQ is only matched by the number of his opposable thumbs
"No balloon and no aeroplane will ever be practically successful."
-William Thomson, 1st Baron Kelvin


If you *have to* pick a genius scientist as your contrarian idol, a towering giant of Lord Kelvin's stature beats the pants off dinky wee Freeman Dyson
denglish
2 / 5 (4) Aug 25, 2015
leetennant? The locals get jobs and feed their family, you hammerhead.

He may prefer child sex slaves, which lots of people turn to when they have no economy.

leetenant's words get even more absurd when one considers the demise of the Maya is considered to be via deforestation. There were no multi-national foundations back then.

He's a liberal; and there is definitely a mental disorder that goes with it, or because of it.

I like the article. its important to be aware of deforestation, and the dove-tail into how it affects animals as the climate changes was nice. It was refreshing to not be exposed to any AGW propaganda.

In the end though, no matter how much we like those furry little cuddly critters, they will adapt to the earth's changes, or die. We can only postpone the inevitable. Being aware of and avoiding industrial scale deforestation is a good way to do that.
gkam
2.3 / 5 (6) Aug 25, 2015
"He's a liberal; and there is definitely a mental disorder that goes with it, or because of it."
---------------------------------------

Why do you oscillate between these insults and your admonitions to everybody else that they are confessions of losing?
leetennant
5 / 5 (4) Aug 25, 2015
Also, as an Australian, I have a good giggle every time an American uses the word 'liberal'. They're usually so myopic they won't get the joke.
docile
Aug 25, 2015
This comment has been removed by a moderator.
HeloMenelo
2.3 / 5 (3) Aug 27, 2015
ohoo, i'm getting goosebumps, this round's going to be fun, can't wait for it to kick into high gear :D

Donglish, shooti Jeffey... get doing what you do best.. we're waiting...dadadaaa..!
SamB
1 / 5 (3) Aug 27, 2015
The only thing that is 'simplified' is the moron who wrote this article. NOTHING in our world is 'simplified'. Even the smallest cell is completely beyond any meaningful comprehension of even the least 'simplified' scientist we can dig up!
HeloMenelo
2.3 / 5 (3) Aug 28, 2015
The only thing that is 'simplified' is the moron who wrote this article. NOTHING in our world is 'simplified'. Even the smallest cell is completely beyond any meaningful comprehension of even the least 'simplified' scientist we can dig up!


By the looks of your rating you are the moron, and dumb at it too... lol... you go sambonkers, (aka donglish)
we know you have nothing else to do with your life than spotting BS on physorg... ;)
HeloMenelo
2.3 / 5 (3) Aug 28, 2015
spotting your own BS haven't come naturally to you yet though... :)
denglish
2.3 / 5 (3) Aug 28, 2015
Why do you oscillate between these insults and your admonitions to everybody else that they are confessions of losing?

I have never said it is a confession of losing. for two reasons:

1. There is nothing to be won.
2. My response to insults is actually a challenge to produce something of value.

Knowing that there is win/lose scenario going on in the liberal brain on this site helps one to understand the emotion immensely.
HeloMenelo
2.3 / 5 (3) Aug 31, 2015
every word you type is a confession of your lunacy, and no you are wrong, there is something to be won, you win bananas all the time :D
HeloMenelo
2.3 / 5 (3) Aug 31, 2015
Monkeys have very impulsive emotions, and you seem to be lacking most of the insecurities posting day and night on this site.

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