In article ,
"songbird" wrote:


my wondering about topsoil is that if it is so good
for overall life then you'd think that by this time (after
millions of years) it would be selected for and there
would be much more of it than there is instead of
what we do find. so my curiousity is engaged on
the topic of the disappearing topsoil.

so much topsoil is lost to erosion and biological
processes that it ends up in the ocean and then
turned into coal and oil but the timescale for that
process is geological (not historical). the balance
needed is the use of the energy to match what the
ocean is capable of storing. we're way past that
(i'm not sure what that amount is), but we'd
know we've gotten there if the ppm of CO2 stablizes
and then starts falling and the ocean acidity does
the same.


songbird

Think of modern agriculture or logging etc as nothing more than strip
mining. Cheap and easy but short term.

http://www.wsu.edu/gened/learn-modul...oil/soil1.html

--
Bill S. Jersey USA zone 5 shade garden
globalvoicesonline.org
http://www.davidmccandless.com/