h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

If you plant a forest and then leave it, it will absorb CO2 until all the trees are fully grown, then it will balance out and produce as much CO2 as it takes in. If you cut down the trees and make them into chairs or paper, making room for more trees to grow, then the forest will start taking in CO2 again.

"then the forest will start taking in CO2 again."

That's a bit misleading. It won't take in any more CO2. But it will, temporarily be a net absorber of carbon dioxide as long as you keep removing trees for paper. The problem with having to keep doing that is pretty obvious.

B

In the natural course of things though, saplings will grow as mature trees decompose.

The only problem with turning the wood into paper or furniture and taking it out of the cycle, is that with each subsequent batch of trees you remove, you are removing a lot of nutrients from the soil. If you think of the chemicals a tree takes in to produce, for the sake of argument, 500 cubic feet of wood, the soil will become increasingly infertile relatively fast.

Master B - I don't understand what taking in CO2 through the roots has to do with it. Trees do take the carbon in - how does it matter whether by root or leaf?

Trees don't need a lot of "chemicals" to make wood. Most of it is just Carbon from the CO2, Hydrogen from water and Oxygen from both.

Those are the main ingredients, but there are a lot of important elements other than those. With each 'harvest' you would be effectively mining the soil of nutrients - important phosphates, nitrates and so on - faster than they would naturally regenerate. I don't see how you could avoid depleting the soil short of pumping in vast quantities of fertiliser.

In effect you'd be taking away fertiliser in the shape of wood, and bringing more fertiliser from other sources - bearing in mind the energy use of extracting fertiliser from whatever the other source is and transporting it and applying it to forest areas - on top of the energy use in doing the same thing transporting and processing wood - letting the wood decompose strikes me as being a much easier and economical method.

Back to anti Wind Farms. This morning's Today programme, or it could have been Farming Today, had an article that said Denmark pays 10p per kw hr for it's electricity, the most expensivve in Europe. Must go check

Somebody has to pay to save the planet.

And like usual, we Danes are getting the bill for it

A forest would likely be inhabited by animals. Who would themselves absorb oxygen and create CO2. So possibly the trees and animals would just create some kind of equilibrium.

Not sure about that - maybe if you had small trees and very big animals?

On a side note, since Denmark changed government, their new environmental objective is no longer to be leaders in Europe, but to be in the middle of the pack. To that end they chopped a lot of env funding, etc etc.

sprout

Wandering, can you explain what you meant earlier when you said that there are now safe ways of disposing of the byproducts from the nuclear energy industry?


One thing that hasn't been mentioned here to do with energy is the need to actually require and use less. We are hugely inefficient when it comes to resources and we still seem to think that we live on a planet with infinite resources. At some point I think we will have to make choices to limit our lifestyles in order to survive.

Going back to windfarms and birds, here's details of a publication on The Daily List from The Stationery Office for today.

Council of Europe.
Nature and environment - 139 Effects of wind farms on birds
- R.H.W. Langston - J.D Pullan - 89p.: 24 cm. - On title page: Convention on the Conservation of European Wildlife and Habitats (Bern Convention).
Price: £9.00 ISBN: 9287155488

Just in case anyone really wants to know, the web address is : http://www.tso.co.uk/bookshop/bookstore.asp?FO=38797

The entry for the above post is near the bottom of the list.

It would be great if everybody could car-share or use public transport and I can see that in big cities it is a real possibility (London Underground for instance) if not essential.

However, the majority (?) of people don't live in big cities with integrated transport systems and, because of work locations, need to travel considerable distances to work (25 miles each way for me).

Nobody I know locally works near me, (notwithstanding different working hours) and my 3/4 hour car journey to and from work (driver only) would be increased to at least 2.1/2 hours each way by using the totally inadequate "out-of-city" transport systems. Not a prospect I would relish (nor many others I suspect).

What would seem to me to be the nub of the problem is that people can no longer work on their doorsteps as they did when places like the mines and steelworks in this area (other industries in other areas of course) were major employers and people need to travel ever greater distances to be able to "sell" their skills.

Taking the alternative of "remote working" as a solution wouldn't neccessarily give much improvement as lots of people working electronically from home would mean that their homes need to be heated/air conditioned through the day (when they may well not have been if working in a traditional way) and a computer still consumes as much electricity at home as it does at a central workplace.

What a dilemma!

Taking up your point about infinite resources and making choices.

Have a look at Wikipedia and look up "Olduvai Theory"
(http://en.wikipedia.org/wiki/Olduvai_theory) if you haven't already.

It's what prompted me to start this conversation in the first place (along with http://en.wikipedia.org/wiki/Global_dimming)

They sure "scared the hell outa me!" (or at least got me thinking)

Fred Hoyle's trenchant comment brings to mind something I've not seen enough of in discussions of energy policy. Particularly in the USA, driven by the Bush Administration's idiocy, is the attitude that we need to extract every last ounce of oil in the ground -- for energy production alone. When what we should be doing is sequestering as much of it as possible, as chemical feed stocks for the world of our umpty-umpted-grandchildren. Those advocating these short-sighted policies must either (1) REALLY believe Armageddon is around the corner, or (2) think the Laws of Therodynamics don't apply to Republicans!