Rainforest Deforestation

Originally posted by loam
Will someone show me a study, not a mere assertion, that says the Amazon was once grassland?

It was. Along with the boreal forests in the northern hemisphere.

It may have been rainforest during the ice age, maybe not. The study referenced above cautions about uncertainty, despite the title and brief abstract.

After the ice age the Amazon basin (but maybe not central Africa -- studies there are still inconclusive) reverted to savannah, and started reforesting about 5000 years ago. After the ice retreated the boreal forest didn't exist, of course, and it had to reforest. There is some evidence the Canadian shield was a temperate forest prior to the last ice age -- ponderosa pine stumps and tree boles have been found on Baffin Island. About 5000 years ago the Great Basin of the western U.S. was a prairie, not unlike the American midwest today. It was not a cold desert. the PJ (pinyon-Juniper) forests that characterize the Great Basin today did not exist then, PJ was all south of the Colorado River. Much of the Sierra Nevada and Cascades did not have significant forest cover until relatively recently. Surveys and analysis clearly show that despite the wild claims of the environmental industry there is as much or more old growth now in the Sierra Nevada mountains as ever existed historically, and up to 3x as much total forest biomass.

An interesting side discussion to global forest changes over time is Douglas-Fir -- the major timber tree of the NW U.S. Prior to the ice age it was also the primary forest tree in northern Europe. Since Europe's mountain ranges run east-west and the North American are north-south, in Europe the advancing glaciers 'pushed' the Douglas-fir into extinction. So is the planting of Douglas-Fir into the forests of Europe introducing an exotic species or is it the re-introduction of a once widespread species?

That is a philosophical question that also impacts the rainforest debate. What time frame are you willing accept when discussing changes?

Ok. Maybe it was. Perhaps it wasnt. Is that really the issue?

Above all, that would be a natural proccess. What we're doing is not. 5000 years or so ago when it happened, we didnt require cures for cancers and diseases and viruses, which we are destroying every single second this continues.

[edit on 21-6-2006 by Shadow88]

take a gander at the med forum sometimes, you'll see why cancer CURES are considered bad for business.....with all the consequences.