On 3/4/2021 2:30 AM, Frank Scrooby wrote:

If and when colonists want to move to soil based agriculture there is a simple-ish solution to the perchlorate problem: H2O. Enough warm water will dissolve and or reactive with the perchlorates, allowing for simple mechanical methods like filtering or evaporation to remove and isolate the offending compounds. If water is not readily available in sufficient quantities good ol' bakin' and shakin' will do to. Setup a solar thermal concentrator that can heat your reaction chamber up to a few hundred odd degrees Kelvin (1000 would be a nice round number) with an extremely high atmospheric pressure (like a few Earth atmosphere equivalents). Expose soil, give it some time to get hot and shake it around to loosen up things. Then reduce the atmosphere pressure via release valve. Between the photons and the rush for lighter elements' atoms to fill the 'vacuum'. What is left behind will be dead and dry, but at least it won't be toxic anymore. And you now have a pressure vessel somewhere filled with the baked off volatiles. Any long term colony is going have uses for those.

For the curious: NASA cooperated with another Organisation on a study called MAGIC (which stands for Mars AGricultural something something). It proposes an automated hydroponic greenhouse as a supplement to crew meals.

Anyway.

Regards
Frank



Came to this posting late. Threaded out of order in my news client. This
makes sense, but in the short term I suspect hydroponics will be the
first setup to grow food, since that is a much simpler setup and
conserves precious water until adequate Martian sources can be secured.

Soil isn't needed to start out.

Dave