[ExI] Top Soil Depletion

[Kelly Anderson]

We hear a lot about global warming and how that's going to ruin the
planet. We even occasionally hear about fossil water tables being
lowered and how that affects agriculture. But we hear much less about
soil depletion and how that might affect the future. Soil takes
thousands of years to accumulate, but is depleted by farming
accelerated erosion to perhaps 1% per year. What that means of course
is that we'll have less than half the soil in the middle of the USA in
80 years than we have now, and that could lead to a difficult
situation for any organic humans left at that point. I wonder if there
would ever be a point where "fossil" soils, such as those in various
deltas around the world, would be mined, somehow desalinated,
reconditioned and put back onto fields... It's a little bit like
taking carbon out of the atmosphere... and that seems unlikely to be a
huge thing anytime soon... but we're here thinking big thoughts about
big futures, so I'm curious if anyone has given this particular idea
any deep consideration.

-Kelly