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Author Topic: How can I build a miniature biosphere capable of supporting a frog?  (Read 17461 times)

Offline Bojiru

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I'll be going to the third year of a Swedish high school and there am I supposed to do a project that falls in my study subjects. Me studying sciences  made the choice easy. But to make a long story really short. The idea is to build a functioning biosphere at the size of a pretty big aquarium and with its biggest animal a frog or toad. The goal of the project is to keep the frog alive without feeding him anything else that can be found in his own enclosed environment. (the airtight, locked glass cage) For this we will need not only water and earth, but a huge amount of small animals who are supposed to keep each other alive and several different species of algae, water plants and land plants.

Now my question is to all of you who know a little about ecosystems and plants. Which plants, algae, mushrooms, animals, insects,  etc would you suggest to put into this space (its around 1-2 m square and 50-70% is going to be water. There is a plateau that stands above the water service where the frog can't come where several more plants can grow) 
I'm looking for plants,algae that grow not to fast but still make a great deal of oxigan. The plants must survive best between 10 and 20 degrees Celsius.
Please keep in mind that the frog (and therefore the plants) only have to survive 1 single year. (after that I will led them free again)
Ideas about different kind of soil and water (PH, amount of magnesium etc) are also really welcome. I ask you this to make sure that I didn't miss something stupid and my frog dies within a week.
« Last Edit: 17/03/2009 23:34:00 by chris »


 

Offline Madidus_Scientia

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I've never designed an ecosystem before but i'm not sure 1-2m square would be big enough to self-sustain a frog?

Can you make it any bigger?
 

Offline Bojiru

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I've never designed an ecosystem before but i'm not sure 1-2m square would be big enough to self-sustain a frog?

Can you make it any bigger?

Its going to stand in a basement with lamps (UV, Daylight and Infrared) to control the amount of light and warmth they will get. But like every basement its pritty cramped down there. Frogs eat larves and flying insects but I'm not sure how much. I can't make the biosphere any bigger than 2.5 m2 at max. Its going to be a small young frog though.
 

Offline RD

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This has been tried with humans living in a sealed greenhouse, (it failed: correct atmosphere could not be maintained) ...

Quote
During the first mission, the oxygen inside the facility, which began at 20.9%, fell at a steady pace and after 16 months was down to 14.5%. This is equivalent to the oxygen availability at an elevation of 4,080 meters (13,400 ft).[14] Since some biospherians were starting to have symptoms like sleep apnea and fatigue, Walford and the medical team decided to boost oxygen with injections in January and August 1993.

Many suspected the drop in oxygen was due to microbes in the soil. The soils were selected to have enough carbon to provide for the plants of the ecosystems to grow from infancy to maturity, a plant mass increase of perhaps 20 tons [16] The release rate of that soil carbon as carbon dioxide by respiration of soil microbes was an unknown that the Biosphere 2 experiment was designed to reveal.
http://en.wikipedia.org/wiki/Biosphere2


http://www.biospheres.com/experimentchrono1.html
« Last Edit: 14/03/2009 16:53:12 by RD »
 

Offline Bojiru

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This has been tried with humans living in a sealed greenhouse, (it failed: correct atmosphere could not be maintained) ...

Quote
During the first mission, the oxygen inside the facility, which began at 20.9%, fell at a steady pace and after 16 months was down to 14.5%. This is equivalent to the oxygen availability at an elevation of 4,080 meters (13,400 ft).[14] Since some biospherians were starting to have symptoms like sleep apnea and fatigue, Walford and the medical team decided to boost oxygen with injections in January and August 1993.

Many suspected the drop in oxygen was due to microbes in the soil. The soils were selected to have enough carbon to provide for the plants of the ecosystems to grow from infancy to maturity, a plant mass increase of perhaps 20 tons [16] The release rate of that soil carbon as carbon dioxide by respiration of soil microbes was an unknown that the Biosphere 2 experiment was designed to reveal.
newbielink:http://en.wikipedia.org/wiki/Biosphere2 [nonactive]


newbielink:http://www.biospheres.com/experimentchrono1.html [nonactive]

Yes I know. The idea is based on the projeckt. And the reason we picked a frog and not a mammel is that we are afraid that the oxigen level would drop to fast and the animal would die even bevore it would die from lack of food. (although we will do everything for the frog to led it surive. Its not like we are going to torture him for fun or something)
 

Offline RD

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With one frog the odds of your experiment failing is very high: if the frog "croaks" it will end your project.

Forget the frog, creating a stable biosphere with plants & microorganisms (& perhaps snails and worms) will be difficult enough. The greater the number of organisms the higher your chance of success: betting everything on the survival of one frog seems doomed to failure.


This may be of interest...

Quote
Building a micro-ecosystem

Objective
Investigate the difficulties in building a stable ecosystem containing higher organisms, such as tomatoes and other green plants, in a relatively small space.

Some important concepts
An Ecosystem: An ecosystem is a community of living organisms interacting with each other and their non-living environment.

community + habitat = ecosystem

For this investigation we will provide a suitably prepared habitat within a sealed glass jar, into which we will place a small community of plants.

Dynamic Equilibrium
The micro-ecosystem in this project contains soil, an atmosphere, green plants, plus innumerable "stowaway" micro-organisms.

The only resource that enters and leaves the ecosystem is energy.

The energy balance is important to an ecosystem. When too much energy enters, the temperature will rise until the energy input is exactly balanced by the heat lost. Conversely, when the energy output (as heat) exceeds the energy input to the system, the temperature of the system will decrease until equilibrium is re-established.
 
In order to achieve stability an ecosystem must attain a state of "dynamic equilibrium". In this state the (average) rate at which resources, such as carbon dioxide, are consumed, is balanced by the rate at which that resource is replaced through the process of recycling.

Experience has shown that in a sample of ten or twelve micro-ecosystems (a class set), some will survive only a few weeks, others will last a few months, and rarely, a few will survive more than a year.

The challenge is to determine, if possible, the reasons for the abrupt failure of some and the remarkable success of others.
http://www.tomatosphere.org/teacher-resources/teachers-guide/grades-8-10/mars-greenhouse.cfm

With many jars (micro-ecosystems) you could try different combinations of plants & animal species and see which survived the longest.
« Last Edit: 18/03/2009 12:53:58 by RD »
 

Offline BenV

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Please keep us updated though - sounds like a fascinating project!
 

Offline yor_on

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Better put a tent over your local pond, put up some coloured flashlights around it and explain that this is your 'forcefield' creating an absolutely 'en closed environment' . Smile happily when not only your frog survives but you also receive the Nobel prize in physics. Be sure to put in the word 'green' and 'stochastic chaos' somewhere, any equations you need can safely be lifted from any physics or meta physics wiki ::))

At least that poor frog will survive, they are a dying breed you know.

--

Ps: if there gets one more, tell them you are cloning..
Or say that it is a frog disco if nothing else helps, that will at least explain the colured lights you're using.

--
In short, you definitively need a bigger environment if you want it to be 'self sufficient'.
« Last Edit: 22/03/2009 21:17:24 by yor_on »
 

Offline Bojiru

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With one frog the odds of your experiment failing is very high: if the frog " newbielink:http://www.urbandictionary.com/define.php?term=croak [nonactive]" it will end your project.

Forget the frog, creating a stable biosphere with plants & microorganisms (& perhaps snails and worms) will be difficult enough. The greater the number of organisms the higher your chance of success: betting everything on the survival of one frog seems doomed to failure.


This may be of interest...

Quote
Building a micro-ecosystem

Objective
Investigate the difficulties in building a stable ecosystem containing higher organisms, such as tomatoes and other green plants, in a relatively small space.

Some important concepts
An Ecosystem: An ecosystem is a community of living organisms interacting with each other and their non-living environment.

community + habitat = ecosystem

For this investigation we will provide a suitably prepared habitat within a sealed glass jar, into which we will place a small community of plants.

Dynamic Equilibrium
The micro-ecosystem in this project contains soil, an atmosphere, green plants, plus innumerable "stowaway" micro-organisms.

The only resource that enters and leaves the ecosystem is energy.

The energy balance is important to an ecosystem. When too much energy enters, the temperature will rise until the energy input is exactly balanced by the heat lost. Conversely, when the energy output (as heat) exceeds the energy input to the system, the temperature of the system will decrease until equilibrium is re-established.
 
In order to achieve stability an ecosystem must attain a state of "dynamic equilibrium". In this state the (average) rate at which resources, such as carbon dioxide, are consumed, is balanced by the rate at which that resource is replaced through the process of recycling.

Experience has shown that in a sample of ten or twelve micro-ecosystems (a class set), some will survive only a few weeks, others will last a few months, and rarely, a few will survive more than a year.

The challenge is to determine, if possible, the reasons for the abrupt failure of some and the remarkable success of others.
newbielink:http://www.tomatosphere.org/teacher-resources/teachers-guide/grades-8-10/mars-greenhouse.cfm [nonactive]

With many jars (micro-ecosystems) you could try different combinations of plants & animal species and see which survived the longest.
The jar idea is a good idea! No really, the school is demanding that we get a lot of paperwork done allowing us to "experiment" on frogs (and everything els alive). Of course our sweet bureaucratic government won't understand that it is for school and therefor NOT AGAINST  the laws. It has taken me alone already 3 hours telephone conversations (with 6 different people) and explaining what I'm planning to do plus countless amount of mails and still we get different answers. We are pretty much still on square one and running out of time. We have 2 weeks left in order to get the paperwork done or otherwise we will be forced to think up a plan B within a week.

I'm guessing that you have a point. The insects that toads and frogs eat have usually a very long larvae (is that the word?)  stadium. But the room itself will be big enough to contain countless amount of organisms (both plants (even mushrooms if we would like)  and animals like worms, flying insects, water insects and everything microscopic). The whole thing is supposed to be ridiculously hard for the amount of points given to it is around the 10% of our final grade.
I hope now that we are allowed to put stuff in jars for school. But they are rather picky about small insects they otherwise try so hard to kill. (no really, only 1 per cent of the animal tests it rejected in Sweden although they are not allowed to test cosmetics on animals they simply test the different chemicals in the cosmetics on rabbits and sutge. Rubbing shampoo in rats eyes is a little cruel but no they are wining about me trying to build a spa for a frog.)
 

Offline Bojiru

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Better put a tent over your local pond, put up some coloured flashlights around it and explain that this is your 'forcefield' creating an absolutely 'en closed environment' . Smile happily when not only your frog survives but you also receive the Nobel prize in physics. Be sure to put in the word 'green' and 'stochastic chaos' somewhere, any equations you need can safely be lifted from any physics or meta physics wiki ::))

At least that poor frog will survive, they are a dying breed you know.

--

Ps: if there gets one more, tell them you are cloning..
Or say that it is a frog disco if nothing else helps, that will at least explain the colured lights you're using.

--
In short, you definitively need a bigger environment if you want it to be 'self sufficient'.

Lol how is it go to survive the winter`? It gets below -20 here! Frog would die (frog icecubes)! or get boiled becouse the tent will get to hot in summar :P
Must say that your post made my day. :D:D:D
 

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