Japanese indoor farm

I.e., there needs to be more animals than just humans in a space settlement. Good.

On Sep 11, 2014, at 4:08 AM, 'Stephen Covey' stephen.covey@deepspaceindustries.com [spacesettlers] wrote:

>
> Speaking of CO2 recycling and oxygen balance, there is a problem: human CO2 production is inadequate. We only consume about 25% of a highly productive crop plant, and much less of some others.
>
> Our metabolism converts that carbon and an equivalent mass of oxygen into CO2, but we need enough CO2 to grow the entire plant, not just the fraction we eat. Basically, we need to burn the other 75% of the plant to produce enough CO2 to grow its replacement.
>
> Of course, there are many forms of burning. Feeding the parts we dont eat to plant-eating animals such as rabbits and goats counts as burning, but on Earth most of such non-flame burning is done by insects and bacterial in the slow process of decay and slow implies that a relatively large fraction of the carbon is tied up in dead materials undergoing the process. A fire is much faster, and easier to control.
>
> The bottom line: we need to produce four times the CO2 that humans exhale to grow the crops we depend on for food; as they grow, those crops will produce four times as much oxygen as we need to breathe. In a large ecosystem we can handle those imbalances by burning (in one way or another) the plant residues of the previous crop to grow the next crop but we must do that carefully and gradually to maintain the balance of CO2, oxygen, people, livestock, and growing plants.
>

On Sep 11, 2014, at 4:08 AM, 'Stephen Covey'
stephen.covey@...
[spacesettlers] <
spacesettlers@yahoogroups.com
> wrote:
Speaking of CO2 recycling and oxygen balance, there is a problem: human CO2 production is inadequate. We only consume about 25% of a highly productive crop plant, and much less of some others.

Our metabolism converts that carbon and an equivalent mass of oxygen into CO2, but we need enough CO2 to grow the entire plant, not just the fraction we eat. Basically, we need to burn the other 75% of the plant to produce enough CO2 to grow its replacement.

Of course, there are many forms of burning. Feeding the parts we dont eat to plant-eating animals such as rabbits and goats counts as burning, but on Earth most of such non-flame burning is done by insects and bacterial in the slow process of decay and slow implies that a relatively large fraction of the carbon is tied up in dead materials undergoing the process. A fire is much faster, and easier to control.

The bottom line: we need to produce four times the CO2 that humans exhale to grow the crops we depend on for food; as they grow, those crops will produce four times as much oxygen as we need to breathe. In a large ecosystem we can handle those imbalances by burning (in one way or another) the plant residues of the previous crop to grow the next crop but we must do that carefully and gradually to maintain the balance of CO2, oxygen, people, livestock, and growing plants.