Here's one of many recent articles about global soil
loss: seattlepi.nwsource.com/local/348200_dirt22.html.
 This article, like most similar articles, refers to
erosion as THE cause of soil losses.

What I'd like to know is, how much of a problem is
subsidence due to organic matter decomposition? 
Shouldn't it be a big part of the problem under
intensive agricultural methods that increase soil
aeration, nutrients, and moisture, while reducing
organic inputs by not fallowing the fields and by
removing much crop residue?

Are there any ECOLOGgers out there who have a ballpark
figure on what percent of soil loss is caused by
decomposition, rather than erosion?

Thanks,
Joe Gathman
Biology Department
University of Wisconsin River Falls

http://seattlepi.nwsource.com/local/348200_dirt22.html
        
Published on Tuesday, January 22, 2008 by The Seattle
Post-Intelligencer
The Lowdown on Topsoil: It’s Disappearing
by Tom Paulson

The planet is getting skinned.

While many worry about the potential consequences of
atmospheric warming, a few experts are trying to call
attention to another global crisis quietly taking
place under our feet.0122 09

Call it the thin brown line. Dirt. On average, the
planet is covered with little more than 3 feet of
topsoil — the shallow skin of nutrient-rich matter
that sustains most of our food and appears to play a
critical role in supporting life on Earth.

“We’re losing more and more of it every day,” said
David Montgomery, a geologist at the University of
Washington. “The estimate is that we are now losing
about 1 percent of our topsoil every year to erosion,
most of this caused by agriculture.”...


      
____________________________________________________________________________________
Be a better friend, newshound, and 
know-it-all with Yahoo! Mobile.  Try it now.  
http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ 

Reply via email to