Plant for Victory!

[Bernie Gunther]

We can't even be totally sure trees will continue to deal with CO2. If the concentration gets too high, problems start to occur with this mechanism.

Check out Peter Cox's presentation at the Exeter conference (bottom of the page) http://www.stabilisation2005.com/programme.html

The Hadley Centre climate-carbon cycle model simulates a “sink-to source” threshold at about 550ppmv.

We're currently pushing 400ppmv ... 380 something last I looked ...

latest figures

Which means we're well on target (accepting the uncertainties in the model) for forests to become a carbon *source* by the end of the century, if we keep on going as we are.

 

[ska invita]

I've just found this article which lists a range of problems related to re-forestation:
http://www.guardian.co.uk/science/story/0,3605,1673265,00.html

- Some of these can be solved by planting native and mixed trees, the issue of carbon being re-emitted by the tree when it dies wouldnt be too problematic if as forests regenerate and would reabsorb as a net effect.

This issue of water however looks very serious - we are already tapping in very deep into the water table, and trees would reduce this further - although they do provide other benefits to the soil, if i remember rightly.

~Of course I agree we should be reducing our carbon use fist and foremost, the question is what can be done to curb global warming whilst these reductions get made. A multi-strategy approach would always be better than a single track one.

Well, I'm dissapointed if your right SnorkelBoy ~ and you probably are: I've fired off an email to growaforset people - I'm sure they'll agree with you, butI'll let you know for certain tommorow.

 

[ska invita]

We can't even be totally sure trees will continue to deal with CO2. If the concentration gets too high, problems start to occur with this mechanism.

Check out Peter Cox's presentation at the Exeter conference (bottom of the page) http://www.stabilisation2005.com/programme.html

We're currently pushing 400ppmv ... 380 something last I looked ...

latest figures

I couldnt even understand the abstract! Could you explain it a little for us Bernie - what ppmv?

EDIT: I've thought about it and I think I get it now... just a little tired - you know how it is

basically if the concentration of CO2 hits 500 ppmv then trees will stop doing their CO2 thing...

 

[ska invita]

~ Predicting that SnorkelBoy is right, lets revise the maths a little ~

My model would have absorbed all the CO2 emissions for a year - but that may be taking things a bit far ~ all we need to do is reduce them to a level that is "safe".

Can anyone venture as to what that might be? ~ I guess its complicated by the fact that different countries produce different quantaties... but is it possible to come up with a rough figure, perhaps a historical one, that was considered adequately low. I'm sure someone has researched this and designated an optimal maximum allowance for us...

 

[Bernie Gunther]

ppmv = parts per million by volume ... that's concentration of CO2 or equivalent (e.g. methane has 20x the effect) in the atmosphere. We're pushing 400 right now, pre-industrial civilisation levels were 280-odd. We're adding about 10ppmv every four years or so at the current rate of emissions.

If we want to limit temperature changes to under 2C, we need to stay under 400ppmv, with reasonably high certainty.

Past 550ppmv, we're very probably (95% or so) in very deep shit. That's before the end of the century at current rates. Of course, there is a lower probability that we're in deep shit much sooner, due to positive feedbacks.

 

[ska invita]

-Yep, Its official, you would have to plant that amount each year... that does mess it up - but lets still try and see how much good that same amount suggested would have - a request for a "safe" level of carbon output for Britain please!

 

[ska invita]

I want to come back to the issue of just how much good replanting 200million trees would do later, but I wanted to look at some of the criticism from this guardian piece:
http://www.guardian.co.uk/science/story/0,3605,1673265,00.html

"His team pooled more than 500 separate yearly observations from studies from five continents which compared planted areas with plots nearby that did not have trees. They report in Science that the plantations had a drastic effect on stream flow. By sucking water out of the ground and evaporating it from their leaves the trees reduced flow by half. And 13% of streams dried up for at least a year. This would have effects downstream where less water would be available for plants and animals."

What about concentrating all growing in the North (anywhere north of Camden!), where there seems to be that much more rainfall -especially Scotland?

 

[ska invita]

There is a group working to restore the Caledonian forest -
http://www.treesforlife.org.uk/tfl.visi.html

Check that link out - I'll post some bits off the page:

The Caledonian Forest once covered 1.5million hectares

Today only 1% of the Forest remains.

"There has been a long history of deforestation in Scotland, and clearance of the land began in Neolithic times. Trees were cut for fuel and timber, and to convert the land to agriculture. Over the centuries, the forest shrank as the human population grew, and some parts were deliberately burned to eradicate 'vermin' such as the wolf. More recently, large areas were felled to satisfy the needs of industry, particularly after the timber supply in England had been exhausted. The widespread introduction of sheep and a large increase in the numbers of red deer ensured that once the forest was cleared, it did not return."

Deer and sheep you see - I thought so! Deer were introduced for the King to hunt, once he'd "cleared" the highlands http://en.wikipedia.org/wiki/Highland_clearances and turned the whole of Scotland into a hunting park.

Scotland with its local tree types " Scots pines, birch, rowan, aspen, juniper" would be the ideal palce to start reforestation - and it shouldnt have any negative effect on the water table or soil quality.
~~~~~~~~~~~~
1,500,000 Hectares is 3,700,000 Acres ( http://www.eddisons.com/property/converter2 )

1 acre = 300 trees
3,700,000 Acres = 1,110,000,000 trees!
Thats sounds like a huge amount - okay lets say they are grown further apart than 12foot x 12 foot gaps (the ratio used to get 300 trees to an acre)

Lets say
1 acre = 200 trees
3,700,000 Acres = 740 million trees!

 

[geminisnake]

I want forests with animals in them, I also would want to see a huge decrease in overall population, but thats another thing.

Haven't had a chance to read this thread yet, but love JTG's idea of the foxhunt/bear thing

But what do you consider to be a forest? There are forests in Northumria and Scotland. There are also animals in these forests.

As for a population decrease!!! You looked at the population per square mile of Scotland recently? Not that I want it any higher thanks

I'll try andremember to read this more later.

 

[Alf Klein]

Planting tress dosen't fix carbon in the long term, because they rot and turn back into carbon dioxide.

Sorry if this has been mentioned already.

 

[gentlegreen]

Planting tress dosen't fix carbon in the long term, because they rot and turn back into carbon dioxide.

Sorry if this has been mentioned already.

And their appetite for CO2 diminishes with age.

So willow or hemp fuel farming looks like the best bet ....

.

 

[Alf Klein]

And their appetite for CO2 diminishes with age.

So willow or hemp fuel farming looks like the best bet ....

.

Why willow and why fuel? Surely growing fuel doesn't reduce carbon dioxide.

What you want is some kind of magic organism that takes in carbon dioxide and produces useful, non biodegradeable material

 

[ska invita]

Natural Forests as opposed to rows and rows of fir trees (which leads to specific problems as outlined in the guardian article: http://www.guardian.co.uk/science/story/0,3605,1673265,00.html ) would be ideal - which would lead to a mixed natural fauna in general - but there is no reason why a combination of foilage couldnt be encourage - I dont know how well willow or hemp would do in Scotland, but Im sure a bit of Ruderalis (isnt that the hemp that grows in the Nrothern Hemisphere) wouldnt go a miss!

Re: the reintroduction of native wild animals (also in Scotland co-incidentaly), here was Monbiots piece on it, but things have moved on since then in terms of consultation, and I dont know where we stand now. http://www.monbiot.com/archives/2004/12/07/bring-them-back-/

and Re: Alf's point about rot, which has been mentioned (!) a net gain in trees would still have a beneficial effect overall for CO2 reduction as forests regenerate - however the limitations of just growing our way out of trouble is duly noted.

Finally re: a population decrease, theres a thread about it here http://www.urban75.net/vbulletin/showthread.php?t=129645&highlight=save+world which was quite interesting...

 

[gentlegreen]

Why willow and why fuel? Surely growing fuel doesn't reduce carbon dioxide.

If it displaces fossil fuel it does.

The alternative is a world made of wicker

.

 

[ska invita]

I accidently posted the wrong link for the guardian story "Tree-planting projects may not be so green" - edited it now, and here is the right one...again
http://www.guardian.co.uk/science/story/0,3605,1673265,00.html

 

[ska invita]

>>>From above post, regarding Caledonion Forest

1,500,000 Hectares is 3,700,000 Acres ( http://www.eddisons.com/property/converter2 )

1 acre = 300 trees
3,700,000 Acres = 1,110,000,000 trees!
Thats sounds like a huge amount - okay lets say they are grown further apart than 12foot x 12 foot gaps (the ratio used to get 300 trees to an acre)

Lets say
1 acre = 200 trees
3,700,000 Acres = 740 million trees!

740 million trees would contain 542million tonnes of CO2 - Britain produces a total of 150 million a year total - this would defintiely buy us a few more years - bearing in mind that we dont need to negate that 150million, but bring it down to a "safe" value...

++Plus I'm sure it would be good for the Scottish tourist economy - and while your there, why dont you get school kids to do the planting on their summer hols, for free - keep the costs down, and also would be a good comeback to Cameron's proposed volutnary service scheme that he's dreamt up - it would also teach city kids about the enivronment and about carbon footprints - and about the danger of bastard sheep!

 

[dylanredefined]

well if they bring wolves and bears back i want a fucking big gun before i go walking again .I like living in a country where there is no wildlife that might eat me .

 

[ska invita]

I know what you mean - but having said that I spent a lot of time in pOland (my motherland!) and there they have huge forests with boars and bison (I dont know if there are any bears left, I think a few, some in the black forest in germany also if i remember rightly) - and its not a big deal - its exciting! they're more scared of you than you are off them etc., - you never really see them.
]

 

[Alf Klein]

I know what you mean - but having said that I spent a lot of time in pOland (my motherland!) and there they have huge forests with boars and bison (I dont know if there are any bears left, I think a few, some in the black forest in germany also if i remember rightly) - and its not a big deal - its exciting! they're more scared of you than you are off them etc., - you never really see them.
]

Bears in the black forest? I think you'll find there aren't any. Your getting them confused with hairy fat Germans.

 

[ska invita]

-Thats the ones! (I'd been drinking schnaps!_

 

[ska invita]

NOTE: This is an old thread resurrected
__________________________________


A good article here showing how utterly unable/unwilling governments are to stop deforestation - and what a crucial part of global warming this is.
http://news.independent.co.uk/environment/climate_change/article2539349.ece

This particular quote is most relevant to this thread:

Richer nations already recognise the value of uncultivated land. The EU offers €200 (£135) per hectare subsidies for "environmental services" to its farmers to leave their land unused.

Its subsidies that are the biggest problem in all this - and it would be so easy to get rid of them - saving us all shit loads of money.

AS if sheep subsidies weren't bad enough, this one above takes the piss.

Anyone know what is mean by "environmental services"?

 

[The Boy]

Anyone know what is mean by "environmental services"?

Is that not what you were proposing yourself earlier in the thread? If farmers are receiving these subsidies to leave their land uncultivated then II'm assuming it's to encourage growth of trees, hedgerows and so on.

Then again this is the EU. Hmmm...Sis works for the EC, think and email to her is in order

 

[Bernie Gunther]

What I'd expect 'environmental services' to mean in this context is e.g. biodiversity letting farmers use less pesticide because pests have a significantly harder time if there's a reserve of predators lurking in a nearby hedgerow. What sometimes happens though is that the farmers take the subsidy, cut down the hedgerow anyway and then try to run the guy who grassed them up for doing so down with their landrover (this actually happened to an eco-hippy of my acquaintance who lived in the hills near Aber)

 

[Poot]

About 10 years ago, in an area not far from where I'm sitting, a local group decided to do some tree planting. They chose an area on the edge of a forest which was very bare and got to work. Unfortunately, what they didn't realise was that they were planting over a sewer main. Gradually the roots took hold of the sewer main and split it. Over some months the sewage poisoned everything within a large area of the forest.

I think it's an admirable idea to plant trees, but you must remember that some land is left for a reason.

 

[_pH_]

Here's my summary of some info from the Forestry Commission (in note form so I hope it makes sense):

FORESTS, CARBON DIOXIDE AND CLIMATE CHANGE

Carbon assimilation and release in woodland/forestry:
Carbon contained in 4 'pools':
living biomass
dead biomass
soil carbon
wood products

All plant material contains ca. 50% carbon – assimilated from CO2 in the atmosphere to form simple sugars which are converted to e.g., starches, lignin, cellulose: ca. 14tC/ha/yr*
Much re-released during respiration: ca. 5.9tC/ha/yr
Other C is accumulated as biomass (stems, branches, roots etc.): ca. 4.0tC/ha/yr
Or added to leaf litter layer: ca. 4.1 tC/ha/yr
Decomposition of leaf litter releases CO2 to atmosphere: unknown
Net removal of CO2: ca. 4.0tC/ha/yr

NB: rate of assimilation in even-aged woodland varies according to lifecycle:
1. Low (or net release after ground preparation and soil organic matter decomposition) during establishment phase
2. High during full vigour phase
3. Levelling off and falling during mature phase
4. Equilibrium during old-growth phase (C assimilation largely balanced by losses to death and decomposition)

Net removal of CO2 therefore varies from ca. 10tC/ha/yr during full-vigour phase to life-cycle average of 3tC/ha/yr

Total weight of carbon sequestered over the life cycle:
1. Old growth woodland: ca. 200t/ha
2. Commercial plantations (where trees are harvested before they reach old-growth stage) ca. 100t/ha (precise figure varies according to silvicultural system in use – CCF most likely to sequester high levels of Carbon; any soil disturbance (e.g., during clear felling and replanting) is likely to lead to carbon loss back to atmosphere (burning/decay/management neglect can → net release of CO2 back to the atmosphere)
3. Soil carbon stock for land under woodland cover = ca. 400tC/ha (UK average)

Planting on peat soils may complicate matters – draining peat may cause decomposition of organic matter → carbon release; but if peat is undrained, anaerobic decomposition releases methane (CH4) – a more potent greenhouse gas than CO2

UK Carbon stocks:
Current area of forests/woodland in UK is 2.8m ha = 150MtC in biomass
Use of wood products as timber should allow for long-term sequestration of carbon – associated carbon pool estimated at 80MtC in the UK (although a higher amount may be in landfill)
On this basis, area of land to be afforested to balance UK CO2 emissions = 50m ha (twice the area of the UK!) assuming average sequestration of 3tC/ha/yr - ¾ of land area would need to be afforested to balance CO2 emissions from car use alone