> > However, the worst offenders are developers who bulldoze and burn forests near growing cities. Subdivisions and shopping centers are spreading out from Atlanta like a mushroom cloud. It's also true of many other cities that I visit on a regular basis. Nashville, Knoxville, and Murfreesboro in Tennessee are good examples. I saw two aerial photos of Murfreesboro made in 1955 and 1995. It was unbelieveable how much forest was gone, not to mention farmland that was covered with houses. The population of that relatively small city went from about 12,000 to almost 45,000 in that period.
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> Now, that's an interesting question and a different issue, I think. Because the question arises, if cutting these trees down to make room for people to live is bad, what are we going to do with the people? The population of the world is always increasing; we have to live somewhere. It's not an easy question to answer.

I agree that this is probably a different issue (if not, I'll make it one :). However, I'd also like to add to the old one about trees and oxygen... I heard somewhere that a great portion of our oxygen gets produced in the ocean, from the bajillions of algae and other oxy-making aqua-plants. I don't know if it's useable to us, but maybe, I don't know.

These days, the phrase, "science fiction is becomming science fact" has become an over-used cliché. New developments like cloning, desktop computers, quantum computers, genetic engineering, nanomachines, teleportation, etc. used to be scoffed at as cheap fiction. Well, it was just cheap fiction... but that doesn't mean that it was impossible.

Not being a physicist, but an avid reader of physics, I have some (probably worthless) ideas of my ideal solution to the problem of an overcrowded earth (if initial costs were not an issue):

1) Make a "beanstalk" out of buckytubes, or carbon nanotubes. Arthur C. Clark suggested a beanstalk years ago (an elevator to space, built atop the tallest equatorial mountain), but it wasn't until a few years ago that we discovered a material capable of withstanding the tidal stresses it would require. Maybe it could be powered by it's motion through the earth's magnetic field as well as by solar energy from the top.

2) Make a lunar spaceport, maybe a lunar beanstalk as well. The lunar regolith (soil) has H2 (nice to have to make water, not to mention rocket fuel), CO2 (which plants can convert to oxygen), and some other volatiles (not to mention the billion-ton ice field at the lunar south pole). Serious metals for construction can be harvested from the asteroid fields, sent into lunar orbit, and construction for space ships would take place in orbit.

The general idea behind it all is to build colony ships to ship off the excess of humanity. It isn't easy to ship off millions, perhaps billions of people using rockets... the sheer amount of fuel required to reach escape velocity makes it just a dream. But if you never have to reach escape velocity in the first place, the rules change a bit. Escape velocity is much, much easier to achieve at the Moon, making it a nice stepping-stone. You can build massive, non-aerodynamic spaceships in orbit, send them off to other worlds and moons to colonize. Europa would be another nice stepping stone (I think it's covered in ice, tho I'm not sure if it was water ice or not).

Eventually, you run out of lunar volatiles; eventually, the asteroids become depleted; eventually, the billion tons of lunar ice are gone... but hopefully, by that time, it won't matter. All our eggs won't be in one basket anymore, and our colonies might help us out if we haven't developed alternate strategies by then.

Maybe this will remain a dream, or just cheap fiction...but maybe, just maybe, it won't.

-Enig"reads alot of sci-fi"ma