Growing enough food for EVERYBODY

If you wanted to start exporting food to Earth you would quickly reach
major problems. Both the nitrogen and the phosphorus cycles in plant
would quickly deplete the soils and atmospheres of any agricultural
unit, and returning these to the orbital soil by blasting them off of
the planet won't be economical. In many cases we are already seeing
this problem on Earth where so many nutrients have been leached from
the soils in the midwest that huge amounts of fertilizers are
manufactured and shipped to the area to offset the nutrients exported
as food.

HUman waste is also a problem with any space habitat but presumably
the of recycling human waste will occur between the space colonies and
the agricultural units. I can envision a situation where entire
industries could spring from this including grading systems, and
commodity and futures markets.

If you want to feed earth you should expect to apply the technology
that we are speaking about on earth. Some level of trade and the
colonies is necessary but moving food and nutrients up and down a
gravity gradient is not realistic.

Bill

--- In spacesettlers@yahoogroups.com, "Xenophile"