Plant trees, not carbon laws

From the University of Michigan

U-M ecologist: Future forests may soak up more carbon dioxide than previously believed

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An aerial view of the 38-acre experimental forest in Wisconsin where U-M researchers and their colleagues continuously exposed birch, aspen and maple trees to elevated levels of carbon dioxide and ozone gas from 1997 through 2008. Credit: David Karnosky, Michigan Technological University

ANN ARBOR, Mich.—North American forests appear to have a greater capacity to soak up heat-trapping carbon dioxide gas than researchers had previously anticipated.

As a result, they could help slow the pace of human-caused climate warming more than most scientists had thought, a U-M ecologist and his colleagues have concluded.

The results of a 12-year study at an experimental forest in northeastern Wisconsin challenge several long-held assumptions about how future forests will respond to the rising levels of atmospheric carbon dioxide blamed for human-caused climate change, said University of Michigan microbial ecologist Donald Zak, lead author of a paper published online this week in Ecology Letters.

“Some of the initial assumptions about ecosystem response are not correct and will have to be revised,” said Zak, a professor at the U-M School of Natural Resources and Environment and the Department of Ecology and Evolutionary Biology in the College of Literature, Science, and the Arts.

To simulate atmospheric conditions expected in the latter half of this century, Zak and his colleagues continuously pumped extra carbon dioxide into the canopies of trembling aspen, paper birch and sugar maple trees at a 38-acre experimental forest in Rhinelander, Wis., from 1997 to 2008.

Some of the trees were also bathed in elevated levels of ground-level ozone, the primary constituent in smog, to simulate the increasingly polluted air of the future. Both parts of the federally funded experiment—the carbon dioxide and the ozone treatments—produced unexpected results.

In addition to trapping heat, carbon dioxide is known to have a fertilizing effect on trees and other plants, making them grow faster than they normally would. Climate researchers and ecosystem modelers assume that in coming decades, carbon dioxide’s fertilizing effect will temporarily boost the growth rate of northern temperate forests.

Previous studies have concluded that this growth spurt would be short-lived, grinding to a halt when the trees can no longer extract the essential nutrient nitrogen from the soil.

But in the Rhinelander study, the trees bathed in elevated carbon dioxide continued to grow at an accelerated rate throughout the 12-year experiment. In the final three years of the study, the CO2-soaked trees grew 26 percent more than those exposed to normal levels of carbon dioxide.

It appears that the extra carbon dioxide allowed trees to grow more small roots and “forage” more successfully for nitrogen in the soil, Zak said. At the same time, the rate at which microorganisms released nitrogen back to the soil, as fallen leaves and branches decayed, increased.

“The greater growth has been sustained by an acceleration, rather than a slowing down, of soil nitrogen cycling,” Zak said. “Under elevated carbon dioxide, the trees did a better job of getting nitrogen out of the soil, and there was more of it for plants to use.”

Zak stressed that growth-enhancing effects of CO2 in forests will eventually “hit the wall” and come to a halt. The trees’ roots will eventually “fully exploit” the soil’s nitrogen resources. No one knows how long it will take to reach that limit, he said.

The ozone portion of the 12-year experiment also held surprises.

Ground-level ozone is known to damage plant tissues and interfere with photosynthesis. Conventional wisdom has held that in the future, increasing levels of ozone would constrain the degree to which rising levels of carbon dioxide would promote tree growth, canceling out some of a forest’s ability to buffer projected climate warming.

In the first few years of the Rhinelander experiment, that’s exactly what was observed. Trees exposed to elevated levels of ozone did not grow as fast as other trees. But by the end of study, ozone had no effect at all on forest productivity.

“What happened is that ozone-tolerant species and genotypes in our experiment more or less took up the slack left behind by those who were negatively affected, and that’s called compensatory growth,” Zak said. The same thing happened with growth under elevated carbon dioxide, under which some genotypes and species fared better than others.

“The interesting take home point with this is that aspects of biological diversity—like genetic diversity and plant species compositions—are important components of an ecosystem’s response to climate change,” he said. “Biodiversity matters, in this regard.”

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Co-authors of the Ecology Letters paper were Kurt Pregitzer of the University of Idaho, Mark Kubiske of the U.S. Forest Service and Andrew Burton of Michigan Technological University. The work was funded by grants from the U.S. Department of Energy and the U.S. Forest Service.

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Brian H

More elements of the elaborate and effective self-regulating nature of the bio-plus-atmosphere.

“Zak stressed that growth-enhancing effects of CO2 in forests will eventually “hit the wall” and come to a halt. The trees’ roots will eventually “fully exploit” the soil’s nitrogen resources. No one knows how long it will take to reach that limit, he said.”
And what results in the study support this conclusion? They already had their expectations proven wrong once, but they turn around and state this as a definite that there is a hard limit to the nitrogen cycle?

“The results of a 12-year study at an experimental forest in northeastern Wisconsin challenge several long-held assumptions about how future forests will respond to the rising levels of atmospheric carbon dioxide blamed for human-caused climate change…”
I think that sums it up. Science is dependent on data not assumptions or model bafflegab.

Terry Jackson

Dang, more “unexpectedly” for the “science is settled” sector.
Numerous experiments and actual business enterprises have shown that CO2 is plant food and increases growth. If they next look at natural succession they might notice that early pioneer plants tend to be nitrogen fixers preparing the soil for their successors.

Greg Cavanagh

It demonstrates the pointlessness of models as predictors, when applied to largely unknown complex multi faceted unstable systems.
Modelling water, air flow, structural members; is easy and reliable. Modelling something unknown and believing the results is dang foolish.

crosspatch

Increased CO2 tends to make many plants more drought tolerant, too. Plants in higher concentrations of CO2 can make fewer stoma which reduces the amount of water they lose.

stephen parker

They are having trouble seeing the wood for the trees

Ken Methven

Pity there isn’t more biodiversity in the AGW perspective. Perhaps we are finally seeing more scientific data being published that dares to state facts rather than state how the facts support the theory.

Patrick Davis

From the article “North American forests appear to have a greater capacity to soak up heat-trapping carbon dioxide gas than researchers had previously anticipated.”
Heat-trapping, really?

Fine, but trees, like people, stop growing after a while, hold roughly constant carbon, then die and release it. So where’s the gain or loss in terms of short geological time spans? Also, it’s not just nitrogen that can become limiting. Any essential nutrient can become limiting, in theory.

Andrew Harding

The problem with planting more forests to soak up CO2 is that it does not shout out to us prols that our respective governments are “doing something” to combat global warming. Windmills, green taxes and propaganda on the other hand do. Sadly this is the intrusive nature of modern politics.
The one good thing that this study may bring about is that when the fallacy of AGW becomes incontrovertible, then governments have a get-out clause to plant more forests (which whether you believe in AGW or not, cannot be a bad thing) and remove all subsidies to windmills. Our landscape will once again look picturesque and the worlds governments will not look stupid for falling for the biggest and most expensive con trick ever perpetrated on mankind

kim;)

Cool!!!
My big brother and I, bought, planted, and tended 90 – 120 trees a year. NOT because of AGW, but for conservation reasons. 🙂

Graeme No.3

Don’t believe this, until the trees are Peer Reviewed!
That won’t be before the next report from the IPCC for sure.

Bravo

Steeptown

The usual false statement “heat-trapping catbon dioxide”. Where do they get the idea that carbon dioxide can trap heat? They’ve been listening to too much false propaganda.

Steve in SC

“Some of the initial assumptions about ecosystem response are not correct and will have to be revised,”said Zak, a professor at the U-M School of Natural Resources and Environment and the Department of Ecology and Evolutionary Biology in the College of Literature, Science, and the Arts.
No shock there
Shylock!
Captain Obvious to the rescue.
Their problem is they are wedded to the CO2 is bad theory and won’t give it up til death.

James Reid

Having been in the habit of planting many hundreds of trees a year (with friends in a Landcare group) I am encouraged by this report.
My thoughts while reading the early part was; “what about nitrogen fixing organisms? Surely there is likely to be a change in the ecosystem to increase Nitrogen in the soil.” Pretty bloody obvious even to a non-scientist like myself.
My prediction is that gradually the story will change… all the CAGW excitement will die down but we will still be left with a disastrous carbon tax to hobble our economy. There will be no acknowledgement by the warmistas that they ever caused the panic. I wonder what the next big catastrophic man made disaster will be that requires taxes to fix?
Mmmmmh… this is hard, everything thing I can think of is already frowned upon. Aha! How about EM transmission? I know this is already a concern for some, but maybe the green movement and the “communication scientists” will model the effects of transmitting TV, radio, internet etc and decide that it is destroying the environment and must be taxed out of existence? Just thinkin’ :-).

Pete in Cumbria UK

Actual research, AND they seem have taken aboard the results. Well done that Zak man. 🙂
As I understand plant foody type things, nitrogen is the limiter especially and mostly because it is so water soluble (it can/does leach out of the soil) – in particular compared to phosphate and potash that bind very strongly to soil particles.
Removing stuff and burning it (Biomass) is a real killer for the medium to long term 🙁
But, nitrogen is easy – and – it took me a while to realise even on my own little patch.
Round here grows a plant called ‘Alder’ (Alnus glutinosa) It grows like nobody’s business where nothing else does.
Reason: Simple, it fixes its own nitrogen.
QED

Climate Dissident

What did they expect? That we lived in a stable climate from thousands of years and that our plants have forgotten about what extra CO2 can do for them?
And why are they expecting additional ozone? At least in North-America and Western Europe, air quality has been improving the last 70 years.

George Lawson

Geoff Sherrington says:
October 13, 2011 at 11:13 pm
“Fine, but trees, like people, stop growing after a while, hold roughly constant carbon, then die and release it. So where’s the gain or loss in terms of short geological time spans? Also, it’s not just nitrogen that can become limiting. Any essential nutrient can become limiting, in theory.”
Presumably over 100 years there would be an infinitely more take up of carbon than that lost on the death of a tree or animal to give a net take up, or is my science wrong.

May..may not..may…may not…
CO2 is like salt and sugar in food, beneficial or harmful according to the latest fad.

Eudoxus

Steepdown asks , “Where do they get the idea that carbon dioxide can trap heat?” and then suggests an answer “They’ve been listening to too much false propaganda.” Is no one here capable of or willing to explain to Steepdown an alternate explanation of where “they” get the idea that carbon dioxide can trap heat?

BioBob

Geoff Sherrington says:
October 13, 2011 at 11:13 pm
————————————————–
Actually, while the individual tree may die, it is replaced by another. Undisturbed high latitude / temperate forests can accumulate organic matter without any known limit. The stems, roots, leaves form a ever increasing organic layer on the forest floor that outpaces the decomposition caused by bacteria, fungus and other cellulose, etc. consumers.
Unless fire is a prominent influence in the ecosystem, it can take many hundreds of years before the accumulation process slows down in many cases. If the ecosystem is very wet, peat will accumulate for thousands of years. These < 80 year old 2nd growth forests are just STARTING this carbon accumulation process..

George Lawson says: October 14, 2011 at 12:52 am reGeoff Sherrington says: October 13, 2011 at 11:13 pm
George, “Infinitely” is a word with mathematical meaning that does not apply to your example. 100 years is NOT a short time on the geological era time scale. Try 10,000 years and redo your sums to find that tree planting makes no great diference. It cannot, in the way you are thinking. Trees take up carbon, they mature, they die, they release it. The only significant way to sequester carbon in trees is to replace a “barren” area with trees whose cumulative carbon weight is greater, then to maintain that carbon uptake FOREVER.
Many people do not realise how badly they are being scammed by schemes to “put more carbon into soil” or to “grow more trees for emission credits”. It’s the next closest move to outright theft. You’re daft if you invest in these credit thingos. Or of criminal mind if you start one.

Baa Humbug

I can’t think of one species of life that doesn’t thrive in the presence of plentiful food. Can anyone else think of one?
Tha vast Taiga forests of the northern hemisphere literally change the composition of the atmosphere during the NH spring/summer

MrV

@Greg Cavanagh
We’ve recently had a fuel-oil spill here, and the model failed to predict exactly where it would come ashore.
http://www.stuff.co.nz/environment/5763638/Locals-get-stuck-into-beach-oil-cleanup
So I’m not sold entirely sold on models of water in the real world. Maybe in more enclosed environments the models work better, but then what is the point?
In the case of the oil it was still better to use observation of where the oil came ashore, than rely on models.

John Marshall

Ann Arbor, a scientist I presume, uses the non scientific phrase ‘-heat trapping’ CO2. It might interest her to know that nothing can trap heat since CO2, like everything else, must obey the 2nd law of thermodynamics.

Kelvin Vaughan

James Reid says:
October 14, 2011 at 12:28 am
Pretty bloody obvious even to a non-scientist like myself
Scientist – Some one who can earn a great deal of money from stating the obvious.

Tipper

Plant trees, that’s nice and I suppose poor old Columbus will get blamed for the
resulting ice age, again .

Pete H

I love trees and have planted many over the 60 years I have lived. There is no requirement for a computer model or 12 year long study to tell us the benefits, especially when using the grant money grabbing line, “rising levels of atmospheric carbon dioxide blamed for human-caused climate change” garbage!

“The only significant way to sequester carbon in trees is to replace a “barren” area with trees whose cumulative carbon weight is greater, then to maintain that carbon uptake FOREVER.” GS Quote
Isn’t that what planting more trees is all about, ie doing the above!?!

mizimi

Geoff Sherrington:
Personally I am not interested at all in what happens in geological times in the future. My future, and that of my children and grandchildren spans perhaps the next 70yrs. So what happens in 1000 or 10,000 years is totally irrelevent to our lives. Geological time spans hold no immediate interest for us and maybe to most of mankind. Here and now and the foreseeable future is what matters to us.
And in this context you are wrong about the time taken to return carbon sequestered by woody plants to decay. 100 yrs is important.
From 1968 to 1998 I lived in a house built with timber cut down in the 1600’s – that timber is now over 400yrs old and the house still stands. Point taken?
In the river bed nearby are stands of bamboo reaching 6m in height; they grow that tall in 2yrs. They die back, leaving the woody stems (30-50mmdia) which rot away very, very slowly. I walk over woody detritus every day which has been there for the past 15yrs or more.
The truth is, woody plants can lock up carbon faster than it is released by natural means and we can lock it up for much longer by using wood for constructional and other purposes.
All it requires is good management.

TFN JOHNSON

Plants take in CO2 thru their stomata – holes in their leaves. The density of these (stomata per sq inch) varies with CO2 concentration. Which can be used to estimate CO2 concenration in prehistory, using leaves preserved anaerobically in lake deposits.
But my point here is to ask if stomata concenration is fixed for a given plant. It must be be during the life of each leaf, but do plants control this genetically, so concentrations stay fixed for the life of the tree? Either way, over time, leaves will grow with fewer stomate as CO2 concentation rises, so obviating the effect found in the post above.

daveburton

The carbon removed from the atmosphere by trees can be sequestered indefinitely, simply by building houses and other wooden structures out of the trees.

Greg Holmes

AGW does not exist, it is a fallacy. Climate models are seriously flawed, as time goes on the data is retro manipulted. Co2 is a fertilizer, everyone knows that, I fail to see this as 12years other than wasted, non science again.

Alan the Brit

OMG! Shock Horror!!!! Trees absorb CO2 & grow faster & better!!! It just cannot be true!! Worse still, O3 doesn’t hinder tree growth in the long term, the bloody trees “adapted”, damn them they should have died! This is “revolutionary” stuff, folks, why has nobody come up with this “revolutionary” idea before? How much did this 11 year “revolutionary” jamboree cost you US taxpayers anyway? Next, they’ll be saying that variable Solar output, coupled with variable UV & Extreme UV, plus low magnetic field strengths & Solar wind, assisted with increased Galatic Cosmic Rays, has an effect on Earth’s Climate, ha, pull the other one, oh puurrleeeze, where do they get these ideas from? Sarc off. 🙂 Someone ought to point out that vegetation has been around for eons because it adapted to Climate Changes of the past, & that if the Earth was, for the sake of argument, a year old Humanity turned up around 8:40pm on New Years Eve!!! Stay sharp & get a grip people, we’re still on a learning curve, & I still prefer the Non-UN Agenda 20, where people were free, had justice, & the right to a life, unfettered by dictators & venal mendacious politicians & Socialists! Oh, & while I am about it, when these scientists find out they were wrong about something, why can’t they just grow a pair & say, “sorry, I was wrong!”. HAGWE everyone, I’ll be cheering for Wales in the morning at the RWC!

Bill Thomson

John Marshall says:
October 14, 2011 at 1:40 am
“Ann Arbor, a scientist I presume, ….”
Ann Arbor is actually the name of a city in Michigan, rather than the name of the author of the article. The author appears to be anonymous.

wayne Job

I do remember in the past that some one mentioned that North America as a whole is a nett carbon sink. The forests you have in the last hundred years have actually increased in size as marginal farm land is abandoned and and people as a habit plant trees. North America may use a lot of fuel and coal but I fear you have been branded as evil CO2 producers but are in reality a carbon sink. Thus these trees are telling us the truth. CO2 monitoring stations on the coast lines and in continental USA may be a cause of severe embarrassment to the AGW crowd. One half an hour after sunrise the CO2 levels in a corn field are depleted, this tells us we are lacking CO2.
Push for more CO2 monitoring over continental USA and Canada and a surprise awaits.

Ask why is it so?

In articles ‘solar climate no longer taboo’ and this one there seems to be a need by the authors to still point to CO2 as the cause of global warming. If trees can feed on the CO2 removing it from the atmosphere, plant lots of trees and stop global warming if that’s the case. My son pumps CO2 into his fish tank to help the plants grow, it’s not new knowledge, but maybe admitting it is.

Ian W

to the rising levels of atmospheric carbon dioxide blamed for human-caused climate change
This is a new level of assumption. ‘Human caused climate change is real and CO2 is being blamed for that climate change’ appears to be a reversal of the logic. Given that the research is based on a falsified hypothesis it would appear to be a waste of funds. You would get more and better information from a forester who would point out that there are several areas of the world where forests have been growing in the same place for centuries – and the nitrogen cycle hasn’t stopped.

Dr. John M. Ware

It seems odd for the UM team to introduce two (in their own words) mutually canceling variables in the same experiment. CO2 and ozone (smog) act (according to them) in opposite directions, so to have them applied simultaneously to the same experimental subjects seems capricious at best. The trees grew in spite of all that; CO2 is plant food.

Matt

This has been my response to AGW proponents who want to wag their finger at me over my carbon footprint. I simply tell them that I own and maintain over 50 acres of forest land in Michigan which sinks far more carbon than my family and I produce. It also produces far more fresh, clean air than we use. That means that, those who don’t own and maintain forest land are actually getting a free-ride off of me. So, if they’re so worried about carbon, go buy land, plant trees and keep it undeveloped – put your money where your big mouth is. Stop being a deadbeat freeloader. Oh, and by the way, you’re welcome.

When the trees “hit the wall” you cut them down and plant new ones. Why do they insist on adding complication?

I told you so. Many times.
The only question is,: Why I should work hard, while these “scientists” lazily walk along their orangeries with cups of coffee, then lazily typing a few word of their trite blah-blah (“Genetic diversity and plant species compositions—are important components of an ecosystem’s response to climate change” — who would have thought? Except there’s no “climate change” to speak of), and then receive their lazy salaries financed by… hapless me.
I am burning with the class hatred. Ignorant parasites. Hang them all high!

Richard111

Trees have had several million years more eco-bio-diversity evolutionary experience than us johnny come latelys. They adapt to climate change, not fight it.

If we consider atmosphere around the earth an enclosed system, then total CO2 available in the system remain constant. Actual problem is population explosion in the third world countries needing fossil fuel, housing resulting in deforestation and uncontrolled emissions CO2 from the factories. In populous cities like Bombay and Karachi, if you walk out wearing white shirt durring peak hours, you will find flakes of carbon deposited on your shirt. The point is the carbon present under the earth crest is coming out and trees are disappearing at very fast pace.The trees will grow faster only if they continue existing, otherwise we will definitely have ever increasing surplus CO2. The soil nitrogen may reduce in your part of globe it will remain surplus in this part of globe. We need a global approach to address this problem.

chris nelli

Higher ozone in the future? What a joke! Seriously. Where did that come from?

I’ll bet the tree rings on those trees are real fat. Maybe tree rings are a better indicator of changing CO2 levels than temperature.

Gilles

The best way is actually to plant more trees and to use more wood, the carbon is sequestrated in the lumber for many years while news trees are growing in place of the used ones.

Brian H

Gilles commented on Plant trees, not carbon laws.

The best way is actually to plant more trees and to use more wood, the carbon is sequestrated in the lumber for many years while news trees are growing in place of the used ones

Yes, and stop recycling paper. Trees are grown as crops for paper. “Recycle your breadcrumbs! Save the wheat!”
Faugh.

MarkW

Where’s the evidence that ozone levels are currently increasing?