How much do houseplants help regarding adding oxygen to your rooms?

[dtilque]

@Colibri

It’s possible, but you would need a large biomass of plants compared to humans, greatly increasing the size of the ship you would need.

That’s one thing SF never mentions. Many ships have a Hydroponics Section for growing food, but never point out that that section would have to be about 90% of the ship to completely do the job. The one exception is Andy Weir’s The Martian, where he’s growing potatoes and has to fill up an entire habitat with plants.

One of the big problems experienced by the Biosphere 2 experiment was gradually falling O2 levels.

That did have a very large amount of biomass in plants. It turned out that the major problem was an unaticipated oxygen (and carbon) sink: exposed new concrete. The lime (calcium oxide) in the cement absorbs CO[sub]2[/sub] as it converts back to calcium carbonate.

[Colibri]

@Jophiel

I always assumed that it was a blast of oxygen from having a trailer packed with plants for three days but, on review of this thread, maybe it was the opposite and we were getting blasted with CO2 from the largely dormant plants in a dark, cool enclosed area.

If they were kept in the dark, they couldn’t have been producing any oxygen, so it would have been CO2.

@dtilque

That did have a very large amount of biomass in plants. It turned out that the major problem was an unaticipated oxygen (and carbon) sink: exposed new concrete. The lime (calcium oxide) in the cement absorbs CO[sub]2[/sub] as it converts back to calcium carbonate.

True, but it was more complex than that. The soils they used were too rich, and supported growth of oxygen consuming bacteria. The real mystery was why this didn’t result in increased CO2, which as it turned out was being absorbed by the concrete. Also, the glass didn’t admit as much light as expected, limiting photosynthesis.

[Leo_Bloom]

@Colibri

[From this cite…]

Do houseplantsincrease oxygen levels?
…From the NASA Fact Sheet we know that air contains 20.95% O2 and 0.04% CO2. If you had enough plants in a room to use up all of the CO2 and convert it to oxygen, the oxygen levels would increase from 20.95% to 21% (ref 3). This increase is difficult to detect and would have no effect on humans. Keep in mind that this increase is the maximum increase possible and assumes plants would use all the CO2 available. In real life the increase is even less…

Ok, switcheroo: what would be the short or long term effect on us without any external CO2?

[Colibri]

@Leo_Bloom

Ok, switcheroo: what would be the short or long term effect on us without any external CO2?

We would starve to death, because green plants would all die.

[I_wasn_t_truly_absent]

@watchwolf49

So, at night when houseplants are respirating they are, in fact, suffocating us? …

yes! haven’t you ever heard about no plants in your bedroom, and, apparently, if you keep ferns you’ll die horribly (not sure why, maybe you’ll just get a slight cough)