New Jungles Prompt a Debate on Rain Forests

[OKIsItJustMe]

http://www.nytimes.com/2009/01/30/science/earth/30forest.html

January 30, 2009

New Jungles Prompt a Debate on Rain Forests

By ELISABETH ROSENTHAL

CHILIBRE, Panama — The land where Marta Ortega de Wing raised hundreds of pigs until 10 years ago is being overtaken by galloping jungle — palms, lizards and ants.

Instead of farming, she now shops at the supermarket and her grown children and grandchildren live in places like Panama City and New York.

Here, and in other tropical countries around the world, small holdings like Ms. Ortega de Wing’s — and much larger swaths of farmland — are reverting to nature, as people abandon their land and move to the cities in search of better livings.

These new “secondary” forests are emerging in Latin America, Asia and other tropical regions at such a fast pace that the trend has set off a serious debate about whether saving primeval rain forest — an iconic environmental cause — may be less urgent than once thought. By one estimate, for every acre of rain forest cut down each year, more than 50 acres of new forest are growing in the tropics on land that was once farmed, logged or ravaged by natural disaster.

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[depakid]

1. Conjures up certain images...

[AlecBGreen]

2. stop chopping virgin growth

:banghead:

The hayfields where I live are growing back into scrub forest. Does that mean its the same as a mature oak-hickory forest? No. It will take 100's of years for my part of the US to revert to its climax community, the same with forests in the tropics. End of story.

[kristopher]

3. Is this really a claim that we now lose only 1/50th as much as

Is this really a claim that we now exploit only 1/50th as much as we 'previously' did.

Previously is only identified by reference to the farmer's field taking 10 years to revert, right?

So the implicit claim is that we now (in 2009) lose only 1/50th as much of the rainforest for "land that was ... farmed, logged or ravaged by natural disaster" as we did in 1999.

Can that claim be true?

[OKIsItJustMe]

4. No, I don't think that's a good read

…

Here, and in other tropical countries around the world, small holdings like Ms. Ortega de Wing’s — and much larger swaths of farmland — are reverting to nature, as people abandon their land and move to the cities in search of better livings.

…

A good deal of land that had been deforested is now growing back (one example being this woman's former farm.) In this one case, she abandoned her farm 10 years ago. That does not mean that all of the land which is "reverting to nature" was abandoned exactly 10 years ago.

[kristopher]

5. Whether it is 10 years or whatever,

the claim is being made that the land returning to forest is 50X the land being put into production.

We don't know how long the lands were in production, but we are given the current ratio of rate of in/out 1:50.

50 years worth of accumulated land area being removed from production all being returned at once is one reading;

the second reading is that the annual rate of removal is 1/50th that of an unexplained annual average;

or it is a combination of the two.

I'm just not clear on what the ratio being thrown out is referring to, are you? I'd just like a better picture of the nature of the demographic shift along with some clear global quantification.

[OKIsItJustMe]

6. This may help answer your questions

http://www.timesonline.co.uk/tol/news/environment/article5505093.ece

January 13, 2009

Apocalypse delayed: tropical forests fight back as farmers flee

Lewis Smith, Environment Reporter

Tropical rainforests are proving more resilient than environmentalists feared, with up to a third of the virgin jungle torn down by loggers and farmers sprouting new trees, scientists announced yesterday.

Aerial and satellite photographs presented at a scientific conference in Washinton show that trees have regrown in up to a third of tropical forests wiped out by loggers and slash-and-burn agriculture. The scientists found that while tropical forests are still being lost at a rate of 13,000 hectares each year – equivalent to 50 football pitches every day – the damage is less severe than some environmentalists have claimed.

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Since the start of the Industrial Revolution, half of the 7.8 million square miles (20 million sq km) of virgin tropical forest has been destroyed. A further 1.9 million square miles has been “selectively logged” with favoured trees being cut down and large clearings created.

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[OKIsItJustMe]

7. The debate: Will tropical species survive?

http://www.stri.org/english/about_stri/headline_news/news/article.php?id=924

The debate: Will tropical species survive?

January 16, 2009

The ongoing debate about the future of the world's tropical rainforests was the central theme of a symposium at the Smithsonian National Museum of Natural History in Washington DC, on Monday, January 12.

The debate featured two senior scientists from STRI, William Laurance and Joseph Wright, who took opposing views of the tropical extinction crisis, and other international experts Elizabeth Bennet, Thomas Rudel, Robin Chazdon, Greg Asner, Claudio Padua and Nigel Stork. SI secretary G. Wayne Clough and Cristián Samper, director of the National Museum of Natural History gave welcoming remarks.

Laurance and Wright have studied the threats to tropical biodiversity for a quarter century. Laurance is perhaps best known for his efforts to predict the impacts of development schemes on the Brazilian Amazon, which sustains 40% of the world's rainforest. His computer models of the future of Amazonia attracted world wide attention to the rapidly growing threats to the region.

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This friendly disagreement within STRI became even more relevant with the discovery that devastated lands were recovering more rapidly than expected, at least in some parts of the tropics, giving the impression that the apocalypse of extinctions would be delayed.

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