In article ,
Doug Freyburger wrote:

songbird wrote:

a large portion of desertification is
from human activities like overgrazing
cows/sheep/goats and removing covering
forests for crops and firewood. some
areas the moisture in the forrests is
part of the local weather cycle. remove
the forrest, change the weather...

Humans have done a large but unknown about of that over the millennia.
The Sahara used to be grassland, as was most of central Asia. How much
was human grazing and farming and how much was natural climate change?
Very hard to tell after the fact.

What is "natural climate change"?

The graph on
http://en.wikipedia.org/wiki/Geologic_temperature_record#Recent_past
indicates that the planet was "naturally" getting cooler.

in China they are trying to reforrest
some areas, but i'm not sure how much
success they've had. i don't think they
have enough moisture or organic stuff
planted along with the saplings so they
bake before they can grow. instead they
probably need an approach like the one
above that starts small and works up
to supporting trees one step at a time.

It would need to be done a step at a time. Getting grasses and shrub
bushes then building generation to generation.
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http://www.youtube.com/watch?v=hYIC0eZYEtI
http://www.democracynow.org/blog/2011/3/7/michael_moore
http://www.youtube.com/watch?v=eZkDikRLQrw
http://www.youtube.com/watch?v=MyE5wjc4XOw