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Author Topic: cleaning up co2 with phytoplankton  (Read 5472 times)

Offline tanian

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cleaning up co2 with phytoplankton
« on: 13/05/2006 00:19:15 »
Environment, eh? Well here's a thought for you all. I've been busily reading all manner of topics about algae used to seed mars for life and how gravity drive works etc. etc., but although these things may seem fascinating, what's the point in seeding a planet if we'll ultimately kill it off anyway? Here's a radical new thought- and one I hope that will cause further debate:

What would happen if we seeded the Oceans of the Earth with huge colonies of phytoplankton?

Would it reduce greenhouse gasses effectively? This has been cited as one of the major causes for the Earth becoming an oxygen rich envirionment in the first place.

And secondly, would it create the further problem of having too much o2 in the environment? What could be the implications of this other than the short term effect of heightened performance in o2 respiring species?

It seems to me we are killing off plant life faster than we can renew it. Plankton grows fast- ever have space monkeys?- so why not replace the greenery we lose with renewable sea borne colonies?

We'd still lose the animal life, but we'd at least keep the air we need to breathe, and possibly our climate too.

People are far too preoccupied with the grander things- like space travel, lunar mining and relativity bending, than they are with the biggest issue of all- will it all come to nothing? Well, not on my watch.

I myself would rather be able to feel the sun on my cheeks. This planet is, after all, the very reason we exist.


 

another_someone

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Re: cleaning up co2 with phytoplankton
« Reply #1 on: 13/05/2006 02:14:43 »
quote:
Originally posted by tanian
What would happen if we seeded the Oceans of the Earth with huge colonies of phytoplankton?



So, how would you do this, and what do you actually mean by 'seeded'?

Phytoplankton are already in the oceans, so they scarcely need any more seeding.  You could talk about creating the condition for greater growth, but what conditions were you thing of changing?

One obvious limiting factor to Phytoplankton growth is the amount of nutrient they have available, and so one way of increasing their growth would be to pump more nutrient into the water.  The best, and simplest, would be to pump more fertiliser, in the form of sewage, out to sea.  I think you might see some resistance to this idea.

Also, the visual effect of having the sea covered in a skin of green algae would not impress too many people, and would risk causing harm to other marine life that rely on sunlight getting through to the deeper waters.

Is there any evidence that increasing the amount of phytoplankton would reduce CO2 further, or is this merely speculation?

quote:

And secondly, would it create the further problem of having too much o2 in the environment? What could be the implications of this other than the short term effect of heightened performance in o2 respiring species?



There can be a problem with too much O2 – if the atmosphere was too rich in O2, it would increase the level of spontaneous combustion (e.g. forest fires).  On the other hand, there is so little remaining CO2 in the atmosphere (even with the extra that we are pumping out), that even if we were to convert all of it to O2, it would be unlikely to make any perceptible difference to the amount of O2 in the atmosphere.

To put some numbers to this.  At present, the amount of O2 in the atmosphere is 209,460 ppm, whereas the amount of CO2 in the atmosphere is 350ppm.  If all the CO2 were converted to O2, the amount of O2 would rise from  209,460 ppm to 209,810 ppm – hardly a major increase.

Would this increase be enough to see an increase in forest fires, which would then have the effect of negating the very effect you seek, by converting this extra O2 back to CO2?  It really depends upon whether the atmosphere is sitting that much on a knife edge that such an effect would come about, but it is improbable.

quote:

It seems to me we are killing off plant life faster than we can renew it. Plankton grows fast- ever have space monkeys?- so why not replace the greenery we lose with renewable sea borne colonies?



What evidence do you have that we are killing off plant life?

The only things I have heard is that we are killing off forests (i.e. big and slow growing trees), but there is still a lot of grass, and other fast growing plant life, that we have relatively little impact on (actually, by killing off the trees, we give more space for other plant life to grow).

quote:

We'd still lose the animal life, but we'd at least keep the air we need to breathe, and possibly our climate too.



Climate will change whatever we do, because the Sun is constantly changing.





George
« Last Edit: 13/05/2006 08:26:24 by another_someone »
 

Offline tanian

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Re: cleaning up co2 with phytoplankton
« Reply #2 on: 13/05/2006 12:18:55 »
You'll have to forgive my generalising, but it was late.

By 'killing off plant life' I was referring to deforestation, because from my admittedly basic understanding of the rainforests there are many forms of plant life involved in those rather fragile ecosystems, all of which is joepardised by deforestation. While it is true that certain species such as grasses could find it easier to survive in open spaces, i.e. deforested areas, I am certain that some species would not survive the transition.

By 'climate change'I was referring to the results of greenhouse gasses and global warming. Such issues are commonly equated with a rise in temperature, rise in sea level etc. (I'm pretty sure we all have the general idea...) and the ill thought out idea is simply to increase photosynthesising species on the sea as we decrease them on the land.

I'm well aware of the size of some plankton colonies, there's a rather fascination exhibition at the Living Coasts centre in Torquay, Devon, that is quite enlightening on the subject (they also have some fantastic penguins). The fact that these colonies regularly grow so large that they can be seen from space quite surprised me.

Plankton are indeed hardy species. It seems to me that they can survive in the fathest most barren parts of the oceans (and very little else does) and respire in a place where very few people are likely to set up a logging company.

The idea is merely speculation, but I've heard the same idea bandied about with regard to altering the atmosphere of mars etc.

To be honest I really don't know enough about the subject.

Generally the thought was using these 'terraforming' notions to counter the effects of greenhouse gasses on our planet, so if you have any ideas be sure to add them.

I would be very interested to see if we have the science to clean up our environment, and to offset some of the damage caused by emmisions before there is too much damage done.
 

another_someone

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Re: cleaning up co2 with phytoplankton
« Reply #3 on: 13/05/2006 14:15:05 »
Firstly, plankton are not a species.  Plankton is a generic term for a wide range of very small sea living organisms that drift with the currents, some animal and some vegetable.  Phytoplankton are the vegetable plankton.  Not all plankton are even full time plankton, some species start their lives as plankton, but grow up to be something bigger.

I am very wary about schemes to manage the Earth's total environment.  It may seem very tempting to create some grand scheme to correct what we perceive as an imbalance that we have created in nature, but if we get it wrong, the size of the disaster we might create could easily dwarf the problem we believe we are trying to fix.

I am not saying that we should not meddle in nature; we always have done on a smaller scale, and as we gain in understanding, we become competent in doing so on a slightly larger scale; just avoid going beyond our reach.  Changing (even if we believe the change is intended to correct something we have done) the whole worlds atmosphere (particularly such a central part of it as the O2/CO2 cycle) is very, very, ambitious; and well beyond our present understanding of the atmospheric processes.

The fact is that the notion that the small amount of CO2 on this planet (even if it increases 10 fold) will create a runaway greenhouse effect is pure theory.  For perfectly understandable reasons, no-one has created an experiment to substantiate the theory.

It has not even been demonstrated that our production of CO2 is in any way influencing the balance of CO2/O2 (this is not to say that we do not product CO2, only that we do not understand how that balance is regulated, and hence whether our production of the gas has any influence upon the balance point – bearing in mind that nature itself has in the past allowed far wider variations of atmospheric CO2/O2 than exists today).  This is why I am not at all certain that increasing the natural photosynthesis capacity of the planet will necessarily make a difference (the assumption here is that simply because we create more CO2, then CO2 lingers in the atmosphere simply because there is insufficient photosynthesis capacity available to convert it to O2 – but if the CO2/O2 balance is something more subtle than that, then simply increasing the photosynthesis capacity would make not the slightest difference to the outcome).

There is actually, in my view, a valid argument that as we run out of oil, we could use nuclear power to convert atmospheric CO2 back into oil (or similar materials that we could use for energy distribution and as feedstock to the petrochemical industry).  Ofcourse, one risk with this might actually be that we might starve some of the plant life of its own raw material (although if we took that much CO2 out of the atmosphere that plants were no longer getting an adequate supply, we might find we starve the nuclear driven CO2 extraction process of its raw material as well; and in any case, if we continue to burn some of the oil produced by this process, then it is not actually permanently removed from the atmosphere).

But, as I said above, the whole notion that CO2 is the driving force for global warming is highly suspect.  What is now generally accepted is that increased solar output has caused substantial warming of the atmosphere in recent centuries; and the only real debate is whether the increase in CO2 (which is real, whatever its cause) adds to the increase in temperature created by increased solar output, or is merely coincidental to (and maybe even caused by) the rise in temperature.  None of the computer models so far that assume a greenhouse effect has demonstrated any consistent accuracy in its forecasts (although, neither has any other computer model – which just shows how much we still do not know about what we are trying to meddle in).




George
 

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Re: cleaning up co2 with phytoplankton
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