🚀 go-pugleaf

In article l2tee4INNcnq@exodus.Eng.Sun.COM, chased@rbbb.Eng.Sun.COM (David Chase) writes:
 
> jdr@starflight.Corp.Sun.COM writes:
> >The analysis is complex, and not amenable to precise estimates. When I say a "few"
> >thousand, it could be as much as 100,000 .. or it could be less then
> >10,000.
> 
> I think you need to look at your numbers again.  I looked at *one
> year*.  People in the US and Europe have lived pretty well for quite a
> few years, not just one.  This indicates to me that your numbers are
> pretty far off -- the time for 10,000 people to do the same damage is
> probably closer to a million years, if not forever (except for the
> fact that 10,000 people is probably not enough to get the right
> economies of scale for recycling and industrial production -- here,
> more is better).
> 
> >Depends on what you mean by a "little bit". 
> 
> By a little bit, I mean enough that each country recycles its own
> wastes (water, sewage sludge, metal, paper, you name it), and
> generates energy from sustainable or very long-term sources (nuclear,
> wind, solar, geothermal, tidal, hydro).  I emphasize "each country"
> because one might hope that if it were feasible for us, then it should
> be feasible for other countries (given a certain level of investment)
> that do not currently enjoy such standards of living.
> 
> David
> 
> 

You have missed the point of the marginality of the impacts of human activity
on the ecosystem and the geosystem. The impacts are not linear.

This is the kind of thing that farmers understand and city folk often do not.
We started in North America with an average of about 3 feet of topsoil, about
200 years ago. Agricultural practices have reduced that to less then 9 inches.
In many parts of the world, people didn't even start with that much, and now
have a lot less.

As the depth of topsoil decreases, it changes in several other attributes as
well. It is more vulnerable to drying that can damage it irreversibly. When it
gets very thin, and no longer has a protective ground cover, any heavy wind or
rain can erode what is left of it in a few days, whereas before it would have
only moved a little of it around a bit. On marginal land in the Southwest you
can still see the marks of wagonwheels or boot prints more than a century later
where biological activity remains suppressed. Overgraze 3 feet of topsoil and
it bounces back within a few years. Do that to 2 or three inches and you get
a desert within days that can take tens of thousands or even millions of years
to recover from.

This kind of thing is easier to appreciate if you visit other countries. I was
once involved in a development project in Brazil, in northern Goias, midway
between Belem and Brazilia. The land there is beautiful: trees, grass, plenty
of water. It looks like East Texas. But looks are deceptive. Whereas in East
Texas you only need an acre or two to support a cow-calf unit, in that area of
Brazil you may need more than 200 acres. The cattle have to spend all their
time eating to get enough nutritional value to survive. If you plant corn or
wheat, the stalk grows tall and beautiful, but the kernals are small, few, and
often empty. There is no way to economically fertilize that land. If you tried,
the soil structure would not retain it -- it would leach out rapidly and
pollute the streams. That is what happened after the first settlers slashed
and burned the land a century ago.

That land in Brazil is more nearly typical of land elsewhere in the world than
is the farmland of Iowa. It is often said that if you plopped an acre of Iowa
farmland in the middle of almost any other country in the world, they would
make a national park out of it.

Everyone should study more about the processes of desertification, which are
occurring not only in the drier parts of the world, but in a larger sense, in
temperate and tropical areas and in the oceans. The recent report from the
United Nations is must reading for anyone concerned about these issues.

A similar problem can be seen in extracting ores. You can get the first
20 percent by digging tunnel mines and producing some tailings. Then you turn
to strip mining and move entire mountains. Finally you are compelled to 
disrupt entire regions to get the remaining 20 percent extractable at a cost
the economy can afford to pay -- if externalities are not considered.

Things work a lot differently while you are pulling apples out of the middle
of the barrel than they do when you start scraping the bottom.

Incidentally, my number of 10,000 is obviously rhetorical. That number could
not support an industrial economy. It would take at least 4 or 5 million to
do that. It is intended to get people to examine the processes involved and
begin to get some kind of ecological numeracy.

Also see my posts on the Limits to Growth and other subjects.

---

starflt@uunet.uu.net, jdr@starflight.corp.sun.com
Jon Roland
Starflight Corporation, 1755 E Bayshore Rd #9A,
Redwood City, CA 94063-4142, 415/361-8141