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A sealed bottle garden thriving after 40 years without fresh air or water

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Re: A sealed bottle garden thriving after 40 years without fresh air or water

#121

Post by Viper007Bond »

asimpletune wrote: post #87
mapt wrote: post #61

So in a symbiotic bacteria/fungi/plant ecosystem, I can understand why CO2, H2O, and O2 might be able to remain in balance. But decomposition produces not only CO2, but CO, CH4, nitrate chemistry... I have trouble understanding why this cycle isn't at least a little bit leaky, since it seems like some of the trace gasses wouldn't automatically have all of the biological, solar, and marine sinks available in nature. I…

The reason it's difficult to understand is because this article is not true.

Don't be silly. This kind of thing is not rare and exists in many schools throughout the country, just not many this old.

Re: A sealed bottle garden thriving after 40 years without fresh air or water

#122

Post by Pitarou »

nmjohn wrote: post #83
mapt wrote: post #61

So in a symbiotic bacteria/fungi/plant ecosystem, I can understand why CO2, H2O, and O2 might be able to remain in balance. But decomposition produces not only CO2, but CO, CH4, nitrate chemistry... I have trouble understanding why this cycle isn't at least a little bit leaky, since it seems like some of the trace gasses wouldn't automatically have all of the biological, solar, and marine sinks available in nature. I…

It really depends on the bacterial flora present in the container. Bacteria are incredibly diverse, and just as one decomposer may be a methanogen [1], a different species of bacteria present may be a methanotroph [2]. So given the right bacterial "mixture," a self-sustaining CH4 cycle is not unreasonable. Additionally, CO is a metabolite for some methanogenic bacteria, specifically in production of acetyl CoA [3]. M…

In other words, the secret to having a viable sealed terrarium is in the compost. Get the right compost, with the right population of bacteria, and the whole thing will run forever.

Re: A sealed bottle garden thriving after 40 years without fresh air or water

#123

Post by bunderbunder »

mapt wrote: post #61

So in a symbiotic bacteria/fungi/plant ecosystem, I can understand why CO2, H2O, and O2 might be able to remain in balance. But decomposition produces not only CO2, but CO, CH4, nitrate chemistry... I have trouble understanding why this cycle isn't at least a little bit leaky, since it seems like some of the trace gasses wouldn't automatically have all of the biological, solar, and marine sinks available in nature. I…

It's almost certainly at least a bit leaky; glass carboys tend to let a surprising amount of gas get in around the bung, which never seals quite perfectly.

That said, even if it falls short of a 100% perfect hermetic seal it's still darn impressive.

Re: A sealed bottle garden thriving after 40 years without fresh air or water

#124

Post by joshvm »

brazzy wrote: post #51
binarycheese wrote: post #6

What if we build a huge sealed bottle garden and send to Mars, can humans live in it!

No. First, every kilogram we send to Mars will be hugely expensive, so low mass will be prioritized over long-term sustainability for research and exploration missions. Second, the plants chosen for bottle gardens are very sturdy and tolerant of non-optimal environments. Humans are a lot more sensitive. If you're interested in the topic, read "The Martian" by Any Weird, a very well-researched SF story about an astron…

Thanks for the recommendation, looks like a good read. Although I was a little disappointed when I found out his name was actually Andy Weir, not Any Weird :P

Re: A sealed bottle garden thriving after 40 years without fresh air or water

#126

Post by zo1 »

Loughla wrote: post #97
asimpletune wrote: post #87

Earlier quoted context omitted.

The reason it's difficult to understand is because this article is not true.

You don't happen to care to elaborate, do you? I've looked all over the google and can't find anything that points to this being false.

I believe they're complaining because it comes from "TheDailyMail". Sometimes people acquire biases towards certain news sources, and then completely ignore pieces from it regardless if it's reasonably true or not, simply by virtue of it coming from "TheDailyMail". Similar to how people grow biases towards Fox/VoA.

Re: A sealed bottle garden thriving after 40 years without fresh air or water

#127

Post by DanBC »

Pitarou wrote: post #122
nmjohn wrote: post #83

Earlier quoted context omitted.

It really depends on the bacterial flora present in the container. Bacteria are incredibly diverse, and just as one decomposer may be a methanogen [1], a different species of bacteria present may be a methanotroph [2]. So given the right bacterial "mixture," a self-sustaining CH4 cycle is not unreasonable. Additionally, CO is a metabolite for some methanogenic bacteria, specifically in production of acetyl CoA [3]. M…

In other words, the secret to having a viable sealed terrarium is in the compost. Get the right compost, with the right population of bacteria, and the whole thing will run forever.

I am interested in the idea of synthetic soils. Arriving on Mars and creating the right mix of sand, silt, and clay is easy enough. But it's the organic matter and biomass that makes soil what it is. Research on this might also have impacts on some parts of developing world where soil quity can be very poor. (Although that's often because anything that could go into the ground to improve soil has other uses).

Re: A sealed bottle garden thriving after 40 years without fresh air or water

#129

Post by wfn »

mapt wrote: post #61

So in a symbiotic bacteria/fungi/plant ecosystem, I can understand why CO2, H2O, and O2 might be able to remain in balance. But decomposition produces not only CO2, but CO, CH4, nitrate chemistry... I have trouble understanding why this cycle isn't at least a little bit leaky, since it seems like some of the trace gasses wouldn't automatically have all of the biological, solar, and marine sinks available in nature. I…

Project idea: start another one of these sealed gardens, but also include various sensors within the bottle/compartment (CO2, CH4, O2, temperature, humidity, pressure, whatnot; but also light levels.)

They can be pretty small and made to fit in nicely. The cheapest way to power them would probably be to use a simple coated electrical cable (through a layer of wax, or through something less leaky), I suppose.

Having them relay data in some fashion while having all the electronics not be exposed to erosion/etc might be a bit tricky.. ideally, just the actual sensor surfaces themselves would reside within; coated wires would all go through the seal, etc. Or, the devices could be (not very easily) shielded, and just the sensor surfaces be exposed..

Of course the most fun way to do this would be to have a whole self-sustaining arduino/whatever running inside, relaying data wirelessly, and having it be powered by small solar panels (would still need to take care of erosion/etc.)

Collect all data, plot it (including the light levels), and see if you can make anything out of it. :)

edit actually, I can now imagine a really large aquarium, with not much light passing into the very middle; for mostly entertainment purposes, it would be nice to also be able to place a cheapo camera there which could take (infrequent, like once every 5min or 20min) timelapses. Another camera with IR lens if needed, for neat composite images.. etc etc. Not sure of possible scientific value re: the latter, but hey!

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