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World News
See other World News Articles

Title: Gore: U.S. Climate Bill Will Help Bring About 'Global Governance'
Source: [None]
URL Source: http://www.climatedepot.com/a/1893/ ... -Bring-About-Global-Governance
Published: Jul 11, 2009
Author: Marc Morano
Post Date: 2009-07-11 09:29:02 by christine
Keywords: None
Views: 1431
Comments: 135

Former Vice President Al Gore declared that the Congressional climate bill will help bring about “global governance.”

“I bring you good news from the U.S., “Gore said on July 7, 2009 in Oxford at the Smith School World Forum on Enterprise and the Environment, sponsored by UK Times.

“Just two weeks ago, the House of Representatives passed the Waxman-Markey climate bill,” Gore said, noting it was “very much a step in the right direction.” President Obama has pushed for the passage of the bill in the Senate and attended a G8 summit this week where he agreed to attempt to keep the Earth's temperatures from rising more than 2 degrees C.

Gore touted the Congressional climate bill, claiming it “will dramatically increase the prospects for success” in combating what he sees as the “crisis” of man-made global warming.

“But it is the awareness itself that will drive the change and one of the ways it will drive the change is through global governance and global agreements.” (Editor's Note: Gore makes the “global governance” comment at the 1min. 10 sec. mark in this UK Times video.)

Gore's call for “global governance” echoes former French President Jacques Chirac's call in 2000.

On November 20, 2000, then French President Chirac said during a speech at The Hague that the UN's Kyoto Protocol represented "the first component of an authentic global governance."

“For the first time, humanity is instituting a genuine instrument of global governance,” Chirac explained. “From the very earliest age, we should make environmental awareness a major theme of education and a major theme of political debate, until respect for the environment comes to be as fundamental as safeguarding our rights and freedoms. By acting together, by building this unprecedented instrument, the first component of an authentic global governance, we are working for dialogue and peace,” Chirac added.

Former EU Environment Minister Margot Wallstrom said, "Kyoto is about the economy, about leveling the playing field for big businesses worldwide." Canadian Prime Minster Stephen Harper once dismissed UN's Kyoto Protocol as a “socialist scheme.”

'Global Carbon Tax' Urged at UN Meeting

In addition, calls for a global carbon tax have been urged at recent UN global warming conferences. In December 2007, the UN climate conference in Bali, urged the adoption of a global carbon tax that would represent “a global burden sharing system, fair, with solidarity, and legally binding to all nations.”

“Finally someone will pay for these [climate related] costs,” Othmar Schwank, a global tax advocate, said at the 2007 UN conference after a panel titled “A Global CO2 Tax.”

Schwank noted that wealthy nations like the U.S. would bear the biggest burden based on the “polluters pay principle.” The U.S. and other wealthy nations need to “contribute significantly more to this global fund,” Schwank explained. He also added, “It is very essential to tax coal.”

The 2007 UN conference was presented with a report from the Swiss Federal Office for the Environment titled “Global Solidarity in Financing Adaptation.” The report stated there was an “urgent need” for a global tax in order for “damages [from climate change] to be kept from growing to truly catastrophic levels, especially in vulnerable countries of the developing world.”

The tens of billions of dollars per year generated by a global tax would “flow into a global Multilateral Adaptation Fund” to help nations cope with global warming, according to the report.

Schwank said a global carbon dioxide tax is an idea long overdue that is urgently needed to establish “a funding scheme which generates the resources required to address the dimension of challenge with regard to climate change costs.”

'Redistribution of wealth'

The environmental group Friends of the Earth advocated the transfer of money from rich to poor nations during the 2007 UN climate conference.

"A climate change response must have at its heart a redistribution of wealth and resources,” said Emma Brindal, a climate justice campaigner coordinator for Friends of the Earth.

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#1. To: christine (#0)

IT was this AGW mess that made me realize people were right about the shadow government and NWO.


… in the past CO2 (or water) was pumped, at some cost, into depleting oil and gas fields to get out more. This will continue, but the taxpayer will contribute to these costs as the oil companies will be paid for taking the unwanted stuff off governments emission balance sheets! No wonder the oil companies are keen on CCS…

farmfriend  posted on  2009-07-11   12:05:13 ET  Reply   Trace   Private Reply  


#2. To: farmfriend (#1)

So Al Gore is the single mantra, drum beater dancing in the streets that made you realize that something was wrong in America?

grace_is_by_our_lord  posted on  2009-07-11   12:14:20 ET  Reply   Trace   Private Reply  


#3. To: grace_is_by_our_lord (#2)

dancing in the streets

Martha And The Vandellas, "Dancing In The Streets"

Those early colored groups were good!

Jethro Tull  posted on  2009-07-11   12:17:14 ET  Reply   Trace   Private Reply  


#4. To: grace_is_by_our_lord (#2)

So Al Gore is the single mantra, drum beater dancing in the streets that made you realize that something was wrong in America?

Smart ass. No, it was the over all global push, and who was pushing, with no supporting science.


… in the past CO2 (or water) was pumped, at some cost, into depleting oil and gas fields to get out more. This will continue, but the taxpayer will contribute to these costs as the oil companies will be paid for taking the unwanted stuff off governments emission balance sheets! No wonder the oil companies are keen on CCS…

farmfriend  posted on  2009-07-11   12:19:54 ET  Reply   Trace   Private Reply  


#5. To: Jethro Tull (#3)

Well, although I want to give you a lot of credit for your fantastic memory about musical groups, I was really attempting to portray the mind-numbed dynamics with these miserable highly vocal Global governance idiots.

Why do you think they want a committee statement suppressing individual rights and freedoms in America?

grace_is_by_our_lord  posted on  2009-07-11   12:23:06 ET  Reply   Trace   Private Reply  


#6. To: grace_is_by_our_lord (#5)

Why do you think they want a committee statement suppressing individual rights and freedoms in America?

Oh pleeeeeeese.......

I'm free to do whatever I want as long as I do everything they say.

Jethro Tull  posted on  2009-07-11   12:25:21 ET  Reply   Trace   Private Reply  


#7. To: farmfriend (#1)

yep..Webster Tarpley called it right on the O presidency and the agenda. i've heard it said by Alex Jones and others that He is the closer.

The smooth criminal transition from Bush/Cheney to Obama

christine  posted on  2009-07-11   12:27:16 ET  Reply   Trace   Private Reply  


#8. To: farmfriend (#4)

No, it was the over all global push, and who was pushing, with no supporting science.

Actually, there is a lot of data to support global warming trends. I don't necessarily believe the major contributor based upon carbon emissions from human technology though. It there is a large number of inputs to the phenomena and human technology is easily modified to change our contributions without government intervention, much less some fantastic boon-dongle bureaucratic mess that is far removed from local geographical areas.

grace_is_by_our_lord  posted on  2009-07-11   12:30:09 ET  Reply   Trace   Private Reply  


#9. To: Jethro Tull (#6)

The goal is to tax your energy requirements so as to limit your consumption. Nothing more to it. Have you considered riding a bicycle to the local grocery store?

grace_is_by_our_lord  posted on  2009-07-11   12:31:58 ET  Reply   Trace   Private Reply  


#10. To: grace_is_by_our_lord (#9)

I walk and jog to various destinations. I'll have you know my carbon footprint has been greatly reduced from it's former self. I now have NO fear of the Carbon Cops.

Jethro Tull  posted on  2009-07-11   12:51:53 ET  Reply   Trace   Private Reply  


#11. To: Jethro Tull (#10)

This is good news. You receive the healthful benefit of extending your life through regular physical exercise while making your purchases of food and other life sustaining products that were trucked in to the grocery store of your choice.

Meanwhile, I hope you have a fatter wallet to pay for the inflated values of the same during this depression; you just may be pushing a wheelbarrow full of greenbacks.

It is a glorious future the government has in store for you.

grace_is_by_our_lord  posted on  2009-07-11   13:07:28 ET  Reply   Trace   Private Reply  


#12. To: grace_is_by_our_lord (#11)

It is a glorious future the government has in store for you.

yes....YES!

When one finally stops the struggle and realized h/she has been hooked and boated, life takes on a new tranquility. Who needs choices? Decisions? They're for experts. It's all good, citizen grace.

Jethro Tull  posted on  2009-07-11   13:25:08 ET  Reply   Trace   Private Reply  


#13. To: Jethro Tull (#12)

But there is much more, Mr. Tull. While you are struggling with your wheelbarrow loaded with greenbacks to offload at the local store, you stop on a nice beautiful day to wipe the sweat from your brow and glance over at the street and notice your local politicians in a police escort on their way to a party, provided by cheering members of the national fascist realigned party which you are not a member of.

And as you took your eye off the wheelbarrow, even so briefly, your wheelbarrow is empty when you look back. Now, you have no money, no food or life providing stock of supplies for life sustaining home life. And the politicians that glanced at you while seeing the theft just smiled as you waved them on.

grace_is_by_our_lord  posted on  2009-07-11   13:38:24 ET  Reply   Trace   Private Reply  


#14. To: grace_is_by_our_lord (#13)

Aren't our rulers entitled to a higher station in life than people of our INK? After all it is they who plan, drive, amend, direct and control us so that our lives will be less stressful. I think some missing wheelbarrow money is a very small price to pay for the true leadership they offer.

Jethro Tull  posted on  2009-07-11   13:51:10 ET  Reply   Trace   Private Reply  


#15. To: grace_is_by_our_lord (#8)

Actually, there is a lot of data to support global warming trends. I don't necessarily believe the major contributor based upon carbon emissions from human technology though. It there is a large number of inputs to the phenomena and human technology is easily modified to change our contributions without government intervention, much less some fantastic boon-dongle bureaucratic mess that is far removed from local geographical areas.

Except that the science doesn't support that either. First, man's contributions are a drop in the bucket and thus irrelevant. That said, the assumption that an increase in carbon emission, anthropogenic or natural, is bad is also a false notion created by the global elite who wish to garner more control and establish the NWO. CO2 is at historic lows for the planet. An increase in CO2 is actually desired, not only for man's benefit but for plants which are a main driving factor in the food chain. There is some anecdotal evidence that the increase in world food production is due to the increase in atmospheric CO2. History has proven that warm periods are beneficial to human culture and growth. The scientific evidence also shows that CO2 increases follow warming.


… in the past CO2 (or water) was pumped, at some cost, into depleting oil and gas fields to get out more. This will continue, but the taxpayer will contribute to these costs as the oil companies will be paid for taking the unwanted stuff off governments emission balance sheets! No wonder the oil companies are keen on CCS…

farmfriend  posted on  2009-07-11   14:15:22 ET  Reply   Trace   Private Reply  


#16. To: christine (#7)

i've heard it said by Alex Jones and others that He is the closer.

I agree that this is the intent. It remains to be seen if we can stop it.


… in the past CO2 (or water) was pumped, at some cost, into depleting oil and gas fields to get out more. This will continue, but the taxpayer will contribute to these costs as the oil companies will be paid for taking the unwanted stuff off governments emission balance sheets! No wonder the oil companies are keen on CCS…

farmfriend  posted on  2009-07-11   14:18:05 ET  Reply   Trace   Private Reply  


#17. To: Jethro Tull (#14)

Well, there is no reason why they shouldn't be exalted within their own minds, is there? After all, they snookered their constituents into believing about government programs that must be sustained at any cost because their ideas are for the people. But the cost at losing our own sovereignty and rights, and liberties?

And are these government programs even sustainable as energy capacity is declining while tax requirements are increasing?

Ever take a peek at the US Federal debt? All do nothing pork and spend as the US Constitution has nothing to do with current rates of spending in rapidly increasing debt and programs that actually have no basis in reality; there hasn't been one US government program since the WW2 that has done anything worthwhile in America. And that same continuing federal debt will double in about 20 years based upon its own current rate.

This means America is on the way towards ensuring slavery of its own citizenry. We will be considered as dogs graveling in back allies fighting over scraps from the table by the same politicians that have created this horror story.

grace_is_by_our_lord  posted on  2009-07-11   14:34:01 ET  Reply   Trace   Private Reply  


#18. To: grace_is_by_our_lord (#17)

Ever take a peek at the US Federal debt?

Actually no. And why should I? Isn't this why we hire Deciders? If I'm not mistaken Washington has a virtual bee hive of Jews that we entrust with our money. I'm OK with that.

Jethro Tull  posted on  2009-07-11   14:46:52 ET  Reply   Trace   Private Reply  


#19. To: farmfriend (#15)

CO2 is at historic lows for the planet.

Cough, spit and BS. Ever see the amazing benefits about American industry (uses about 25% of all non renewable energy from around the world) hoovering over major population centers? Smog was rampant through the 40s - 70s in America.

Today, smog is decreasing but it is still prevalent in the atmosphere. It is composed largely of CO2 which is a major by-product of energy use, particularly with carbon based fuels such as oil and gasoline. Smog pollution has been identified by most as particulate matter suspended in the release of CO2 emissions; but smog is really CO2.

Ever since the belching plumbs, as by the Iron Horses, of smoke during the early days of the industrial revolution since the mid 1800s, CO2 has been steadily increasing.

grace_is_by_our_lord  posted on  2009-07-11   14:50:20 ET  Reply   Trace   Private Reply  


#20. To: grace_is_by_our_lord (#17)

It is your fault buckeroo. If it wasn't your love for your god Obama that took us down this path. It's your fault buck.

Old Friend  posted on  2009-07-11   14:51:16 ET  Reply   Trace   Private Reply  


#21. To: Jethro Tull (#18)

Actually no. And why should I? Isn't this why we hire Deciders? If I'm not mistaken Washington has a virtual bee hive of Jews that we entrust with our money. I'm OK with that.

There is a lesson here, by your own admission. Figuratively, you can not allow others to perform your own critical thinking.

grace_is_by_our_lord  posted on  2009-07-11   14:56:50 ET  Reply   Trace   Private Reply  


#22. To: grace_is_by_our_lord (#21)

Figuratively, you can not allow others to perform your own critical thinking.

Ummmm....in our NEW AmeriKa, critical thinking is strongly discouraged.

Jethro Tull  posted on  2009-07-11   15:27:43 ET  Reply   Trace   Private Reply  


#23. To: Jethro Tull (#22)

Yeah, And it is too late, too. From here on, it is nothing more than a futile exercise of mental masturbation.

grace_is_by_our_lord  posted on  2009-07-11   15:41:00 ET  Reply   Trace   Private Reply  


#24. To: grace_is_by_our_lord (#23)

It's time.

Send in the clowns.

Jethro Tull  posted on  2009-07-11   16:01:07 ET  Reply   Trace   Private Reply  


#25. To: grace_is_by_our_lord (#19)

Cough, spit and BS. Ever see the amazing benefits about American industry (uses about 25% of all non renewable energy from around the world) hoovering over major population centers? Smog was rampant through the 40s - 70s in America.

Today, smog is decreasing but it is still prevalent in the atmosphere. It is composed largely of CO2 which is a major by-product of energy use, particularly with carbon based fuels such as oil and gasoline. Smog pollution has been identified by most as particulate matter suspended in the release of CO2 emissions; but smog is really CO2.

Ever since the belching plumbs, as by the Iron Horses, of smoke during the early days of the industrial revolution since the mid 1800s, CO2 has been steadily increasing.

Ah my dear, you need to stop drinking that Kool-Aide and learn the real facts and history of CO2. BTW, there is one country that has bypassed the US in CO2 production and the US had less growth in emissions than all the countries who signed and implemented Kyoto.

I'll get you hooked up with the science if you wish. My knowledge and access has grown since our days of posting at LP.


… in the past CO2 (or water) was pumped, at some cost, into depleting oil and gas fields to get out more. This will continue, but the taxpayer will contribute to these costs as the oil companies will be paid for taking the unwanted stuff off governments emission balance sheets! No wonder the oil companies are keen on CCS…

farmfriend  posted on  2009-07-11   16:07:04 ET  Reply   Trace   Private Reply  


#26. To: Jethro Tull (#24)

So what is the driving force behind Gore's Global governance? Is it an actual concern for planet resources as he enjoys the comforts of his private jet as he peers down and over us minions and makes his mind up to change the thinking of Americans? Or is he just looking for another government job that allows him to sustain his own quality of life?

grace_is_by_our_lord  posted on  2009-07-11   16:09:06 ET  Reply   Trace   Private Reply  


#27. To: grace_is_by_our_lord (#26)

The answer is rests at the Presidio, in the spotted cranium of Gorbachev.

Jethro Tull  posted on  2009-07-11   16:14:26 ET  Reply   Trace   Private Reply  


#28. To: Jethro Tull (#27)

Not at all. There is no "higher" power unless you believe in them. The answer rests within your own skull, do you believe in yourself?

grace_is_by_our_lord  posted on  2009-07-11   16:37:59 ET  Reply   Trace   Private Reply  


#29. To: farmfriend (#25)

Ah my dear

I am flattered by your personal compliment hugging me.

The rates of human consumption stripping the environment for energy and food and other resources is unsustainable. Governments can't sustain the lack of resources around the world by legislation. And believing in an infinite playground unfettered by 6.7Bn people on the planet isn't either.

For America to get back on track about the nation is to diminish personal energy consumption and forget this crazy idea of unsustainable growth rates which has destroyed America's quality of life.

grace_is_by_our_lord  posted on  2009-07-11   16:45:57 ET  Reply   Trace   Private Reply  


#30. To: grace_is_by_our_lord (#29)

For America to get back on track about the nation is to diminish personal energy consumption

Why? What is it about diminishing personal energy consumption do you think would help the situation? CO2 production is a benefit to both humans AND the environment. How is changing that going to help?


… in the past CO2 (or water) was pumped, at some cost, into depleting oil and gas fields to get out more. This will continue, but the taxpayer will contribute to these costs as the oil companies will be paid for taking the unwanted stuff off governments emission balance sheets! No wonder the oil companies are keen on CCS…

farmfriend  posted on  2009-07-11   16:50:29 ET  Reply   Trace   Private Reply  


#31. To: grace_is_by_our_lord, Jethro Tull (#26)

So what is the driving force behind Gore's Global governance? Is it an actual concern for planet resources as he enjoys the comforts of his private jet as he peers down and over us minions and makes his mind up to change the thinking of Americans? Or is he just looking for another government job that allows him to sustain his own quality of life?

He wants to be part of the Bilderberger in crowd. Sadly for all his wealth he is just not wealthy enough.


… in the past CO2 (or water) was pumped, at some cost, into depleting oil and gas fields to get out more. This will continue, but the taxpayer will contribute to these costs as the oil companies will be paid for taking the unwanted stuff off governments emission balance sheets! No wonder the oil companies are keen on CCS…

farmfriend  posted on  2009-07-11   16:52:39 ET  Reply   Trace   Private Reply  


#32. To: farmfriend (#30)

I thought OXYGEN was a benefit to mankind. What makes you think CARBON_DIOXIDE is? When you breathe the in the aire around you take in OXYGEN. When you exhale, you remove CARBON_DIOXIDE.

And there is only a limited amount of resources; certainly natural ones such as food and the environment around us. CO2 has shown on a consistent basis to make agricultural products low in vitamins and nutrients; yet within oxygenated environments agricultural products have shown large manifestations of the same nutrients in wheat, corn and certainly fruits and other vegetables.

grace_is_by_our_lord  posted on  2009-07-11   17:02:15 ET  Reply   Trace   Private Reply  


#33. To: grace_is_by_our_lord (#32) (Edited)

What makes you think CARBON_DIOXIDE is?

The human mind works better at higher CO2 concentrations thus our military subs keep the concentrations higher for performance reasons. Greenhouses keep CO2 at 1000 ppmv.

CO2 has shown on a consistent basis to make agricultural products low in vitamins and nutrients; yet within oxygenated environments agricultural products have shown large manifestations of the same nutrients in wheat, corn and certainly fruits and other vegetables.

I think you'll have to back that one up, please.


… in the past CO2 (or water) was pumped, at some cost, into depleting oil and gas fields to get out more. This will continue, but the taxpayer will contribute to these costs as the oil companies will be paid for taking the unwanted stuff off governments emission balance sheets! No wonder the oil companies are keen on CCS…

farmfriend  posted on  2009-07-11   17:13:38 ET  Reply   Trace   Private Reply  


#34. To: farmfriend (#33)

Here is one: http://www.nwrc.usgs.gov/climate/fs90_97.pdf my search engine is running wild!

grace_is_by_our_lord  posted on  2009-07-11   17:23:49 ET  Reply   Trace   Private Reply  


#35. To: farmfriend (#33)

SCOPE 56 - Global Change: Effects on Coniferous Forests and Grasslands, Chapter 9, Elevated Carbon DioxideHere is two:

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SCOPE 56 - Global Change: Effects on Coniferous Forests and Grasslands

9

Elevated Carbon Dioxide, Litter Quality and Decomposition

J. M. MELILLO
The Ecosystems Center, Marine Biological Laboratory, Woods Hole, USA

9.1 INTRODUCTION

Plant litter decomposition is one of the important biogeochemical processes that could be affected by these aspects of global change. One long-standing hypothesis in the global-change literature is that elevated CO2 will result in the production of plant litter with wide carbon to nitrogen (C/N) ratios and perhaps elevated concentrations of structural compounds such as cellulose and lignin (Melillo 1983; Strain and Bazzaz 1983; Melillo et al. 1990). In addition, this 'nitrogen- poor', litter that is enriched in structural compounds will decompose slowly. The slowed decomposition will, in turn, reduce nutrient cycling rates and, in the long term, will diminish the plants' ability to respond to elevated CO2 in a classic negative feedback.

9.2 FACTORS THAT CONTROL LITTER DECOMPOSITION RATE 

More than a half century ago, Tenney and Waksman (1929) developed a 'short list' of factors they considered primarily responsible for controlling the rate of plant litter decay. Included in the list were substrate quality and climate. Research on decomposition processes since then has supported their choices.

Indexes of substrate quality include element concentrations and concentrations of various classes of organic compounds. A high correlation between initial nitrogen concentration and decomposition rate has been demonstrated by a number of researchers (e.g. Bal 1922; Hill 1926; Waksman and Tenney 1928; Waksman and Gerretsen 1931; Monnier and Jeanson 1964; Satchell and Lowe 1966; Witkamp 1966; Cowling and Merrill 1966; Kaushik and Hynes 1971; Harrison and Mann 1975; and Taylor et al. 1989). Litter mass loss has also been correlated with initial lignin concentration (e.g. Cromack 1973; Cromack and Monk 1975; Fogel and Cromack 1977; Berg and McClaugherty 1987; Aber et al. 1991). In some studies, the initial lignin to nitrogen ratio has been shown to be  the best predictor of plant litter decay rate (e.g. Melillo et al. 1982; Aber and Melillo 1982; Melillo et al. 1984). In an attempt to unify these various interpretations of what component of initial chemistry of litter controls its decay rate, Taylor et al. (1989) have proposed a two-phase exponential model, in which initial nitrogen content controls decomposition rate early in the decay sequence, while lignin is the controlling factor later in decay.

Climate regime, including both temperature and moisture, is also an important controller of decay rate. In well-drained grasslands and coniferous forests, the general rule is the warmer and wetter the site, the more rapid the litter decay rate (e.g. Meentemeyer 1978). Many models of plant litter decomposition have integrated climate and litter quality controls on litter decay rate (Bunnell et al. 1977a, b; Meentemeyer 1978; Parton et al. 1987; Rastetter et al. 1992).

9.3 CARBON DIOXIDE ENRICHMENT AND PLANT LITTER QUALITY  

Changes in litter quality may be induced by an increased level of atmospheric CO2. Observed litter quality changes include a reduction in nitrogen concentration and, in a few cases, increases in lignin concentration. A reduction in nitrogen concentration in leaf litter has often been found in CO2 enrichment experiments with trees (e.g. Melillo 1983; Norby et al. 1986; O'Neil et al. 1987; Lux moore et al. 1986; Brown 1991; Kohen et al. 1992; Boerner and Rebbeck 1993; Johnson 1993; Cotrufo et al. 1994) and with grasses (e.g. Overdieck and Reining 1986; Larigauderie et al. 1988). Most of the experiments involving trees are with deciduous species because the deciduous tree experiments require much less time to conduct than experiments with coniferous species. In CO2-enrichment research designed to study the litter-quality issue, it is important that leaves or needles be permitted to senesce naturally so that the process of nitrogen reabsorption can occur prior to abscission. In conifers as much as 50% of the nitrogen in green needles may be reabsorbed (e.g. Prescott et al. 1989). Time to natural abscission is several years for conifers, while it is less than a year for deciduous species. Carbon dioxide experiments in which needle senescence and abscission are induced by drying or some other technique, limit nitrogen reabsorption and so mask any reduction in nitrogen concentration in litter. For example, in their CO2-enrichment study Cotrufo et al. (1994) observed that the nitrogen concentration in spruce needles litter was very high, and unlike the deciduous species studied. They suggested that the reason for this difference was related to the fact that the deciduous species were allowed to abscise naturally, while the spruce needle litter was obtained by forced drying.

Even when the experimental artifact of induced senescence and abscission is avoided, the nitrogen concentration in the litter of nonwoody plants does not always appear to decrease under elevated CO2 or decreases only slightly. Results indicating no increases or slight decreases have been reported for a salt marsh (Curtis et al. 1989) and a tall grass prairie (Kemp et al. 1994).

Table 9.1 Initial litter chemistry (%)


Nitrogen level (relative):

High
Low




CO2 level (ppmv):
Species

Element/ compound
350
700

350
700


Ash

N

Lignin

1.01

10.67

0.64

10.63

0.43

7.09

0.45

6.83

G. birch

N

Lignin

0.51

13.24

0.39

12.60

0.34

10.91

0.40

11.49

Oak

N

Lignin

1.12

17.54

0.50

16.58

0.44

14.50

0.46

14.16

R. maple

N

Lignin

0.59

8.12

0.41

11.47

0.34

6.35

0.31

9.33

S. maple

N

Lignin

0.94

9.34

0.56

11.17

0.90

11.13

0.60

8.43

Y. birch

N

Lignin

1.03

12.94

0.63

12.62

0.58

10.37

0.51

10.97


The circumstances under which plants produce nitrogen-depleted litter upon exposure to elevated CO2 are not well defined. One argument is that in nitrogen-deficient soils, plants exposed to elevated CO2 will change their nitrogen-use efficiencies (plants will incorporate more carbon into plant tissue per unit nitrogen incorporated) and that this change will persist in the litter (Norby et al 1986; O'Neil et al. 1987). There is evidence, however, that decreased nitrogen concentration can occur in plant material exposed to elevation CO2 at both low and high levels of soil nutrition (Cotrufo et al 1994).

There are several reports of an increase in lignin concentration in litter from plants grown in high CO2 atmospheres. These increases are usually only a few percent (Melillo 1983; Boerner and Rebbeck 1993; and Cotrufo et al 1994). In contrast, Norby et al. (1986) found a decrease in leaf-litter lignin from oak seedlings grown in elevated CO2. In this experiment, the lignin concentrations of both the 'treated' and 'control' plants were unusually low for leaf litter of an oak species, perhaps because the leaves were from very small seedlings. In a CO2-enrichment experiment I conducted with Bazzaz and his students at Harvard, we found small changes (positive and negative) in leaf litter lignin concentrations depending on species and treatment (Table 9.1).

In summary, there is widespread experimental evidence for a reduction in nitrogen concentration of litter from plants grown in an enriched CO2 environment. The evidence for changes in lignin content is not as clear-cut. The nitrogen changes imply reductions in litter decay rates. There is a small amount of experimental evidence from laboratory and field decomposition studies that  supports the notion of reduced decay rates following CO2-induced litter quality changes. This evidence is reviewed next.

9.4 DECAY OF LITTER FROM PLANTS GROWN IN A CO2-ENRICHED ENVIRONMENT  

I know of five decomposition studies that have followed the decay rate of litter from plants grown in a CO2-enriched environment. Three are laboratory studies and two are field studies. One of the laboratory studies (Boerner and Rebbeck 1993) combined effects of elevated ozone twice and CO2 on the litter quality of Tulip poplar (Lircodendron tulipifer L.). The litter was then decayed in laboratory tanks that were continuously stirred. The effect of CO2 enrichment on litter quality was about a 30% reduction in nitrogen concentration and a large ( ~ 2.5 x) increase in the lignin to nitrogen ratio. Over the course of the first year of the study, decay rate was much lower in the treated litter than in the control one.

Another laboratory decay study was done in soil-free microcosms, where Cotrufo et al. (1994) used three deciduous litter types (ash, Froximas excelsior L.; birch, Betula pubescens Ehrb.; and Acer pseudoplatanus L.) and one coniferous species (spruce, Picea sitchensis (Beng.) Carr.). The plants were grown under both treated (600 ppmv CO2) and control (300 ppmv CO2) conditions. In the decomposition part of the study, Cotrufo et al. found a significant decrease in respiration and decomposition rates in the litter materials from the treated (CO2-enriched) plants.

The above two sets of laboratory results are in agreement with those found by Cofiteaux et al. (1991) for litter from chestnut seedlings grown in elevated CO2. When the litter was incubated in the laboratory with only microflora and protozoa, the litter from plants grown at elevated CO2 decayed slower than did the litter from plants grown at ambient CO2. When Cofiteaux et al. added a more complex fauna, total carbon loss was actually increased for CO2-enriched litter above the litter produced at ambient CO2. These latter results are difficult to interpret, but they do highlight the need for experiments investigating litter decomposition under field conditions.

In a field decomposition study in tall grass prairie, Kemp et al. (1994) found that litter from plants grown at elevated CO2 decomposed at about the same rate as litter grown at ambient CO2. The grass species studied were Andropogon gerardii, Sorghostum mutans, and Poa pratensis.

I have worked with Bazzaz and his students on a field decomposition study at the Harvard Forest. We used litter from six species of deciduous plants grown in full light, at either high or low nitrogen availability, and at either ambient (350 ppmv) or doubled (700 ppmv) CO2. Litter from each of the various combinations of treatments was incubated in mesh bags placed on the floor of a deciduous forest site. After one year of decay in the field, we found that within a nutrient treatment, litter materials from plants grown at elevated CO2 generally had lower decay rates than those grown at ambient CO2. The magnitude of the effect varied among species and there were a few exceptions to the general trend (Table 9.2).

Table 9.2 Observed decay rate at 1 year

Nitrogen level (relative):
High

Low



CO2 level (ppmv):
Species

350

Decay rate

700

(-k)

350

700


Ash
0.77

0.350.930.80
Grey birch

0.73
0.540.901.03

Oak
0.41
0.41

0.350.24
Red maple

0.78

0.470.600.61
Stripped maple

0.72
0.450.940.74

Yellow birch
0.87
0.41

0.950.65

9.5 WARMING AND DECOMPOSITION RATE  

If warming accompanies increases an atmospheric CO2, the temperature increase, which is likely to increase decay rate, may offset the negative feedbacks to plants associated with the CO2-induced decrease in litter quality. At the Harvard Forest, my colleagues and I have conducted a soil warming experiment to determine the potential effects of this aspect of climate change on soil organic matter decay and on nitrogen availability.

Results from the first year of study (July 1991 through June 1992) at the Harvard Forest soil warming experiment indicated that heating increased emission of CO2 and nitrogen mineralization. We estimated CO2 fluxes to be approximately 7100,7900, and 11100 kg C ha-1 yr-1in the control, disturbance control, and heated plots, respectively; this represents an increase due to warming of approximately 3200 kg C ha-1 yr-l. Nitrogen mineralization was doubled in the forest floor plus the top 10 cm of the mineral soil. During the first growing season, we observed that in the forest floor, heating increased the average net mineralization rates from 1.02 to 2.47 mg N kg-1 d-1. In the mineral soil, heating increased the average net mineralization rates from 0.09 to 0.19 mg N kg-1 d-1. No nitrification was observed in either forest floor or the mineral soil in any of the treatments.

Results from the second year of study (July 1992 through June 1993) indicated that warming had a much less dramatic effect on CO2 flux, but a sustained dramatic effect on nitrogen mineralization. We estimated CO2 fluxes in the second year to be approximately 6800, 7600, and 8700 kg C ha-1 for control, disturbed control and heated treatments, respectively. Nitrogen mineralization rates remained doubled. Again, no nitrification was observed in either the forest floor or the mineral soil.

One interpretation of the differences in the CO2 response (heated versus disturbed control) between the first and second years versus the constant response in nitrogen mineralization is as follows:

(a) there are two major soil organic matter (SOM) pools a fast and a slow pool; 

(b) the fast pool contains high C:N ratio material (e.g. recent litter) the decay of fast pool material results in large CO2 losses per unit of material processed and small net nitrogen release in the mineralization process;

(c) the slow pool contains low C:N ratio material (e.g. metastable humus) the decay of the slow pool material results in a smaller loss of CO2 per unit of material processed and large net nitrogen release in the mineralization process. As elevated soil temperature increases the rate of decay in the slow pool, both carbon (as CO2) and nitrogen (as inorganic N) are released. The nitrogen then becomes available to be taken up by plants. Since the C:N ratio of plant material is substantially larger than the C:N ratio of SOM in the slow pool, warming may lead to increased carbon storage in the ecosystem. The magnitude of such an increase would, of course, depend on how plant carbon balance is affected by other components of climate change including the availability of water and the effect of increased temperature on both photosynthesis and respiration.

9.6 REFERENCES

Aber, J. D. and Melillo, J. M. (1982) Nitrogen immobilization in decaying hardwood litter as a function of initial nitrogen and lignin content. Can. J. Bot. 60,2263-2269.

Aber,J. D., Melillo, J. M. and McClaugherty, C. A. (1991) Predicting long-term patterns of mass-loss, nitrogen dynamics and soil organic matter formation from initial litter chemistry in forest ecosystems. Can. J. Bot. 68,2201-2208.

Bal, D. V. ( 1922) Studies on the decomposition of some common green manuring plants at different stages of growth in the black cotton soil of Central Provinces. Agr. J.lndia 17, 133-155.

Berg, B. and McClaugherty, C. (1987) Nitrogen release from litter in relation to the disappearance of lignin. Biogeochemistry 4,219-224.

Boerner, R. E. J. and Rebbeck, J. (1993) Decomposition of hardwood leaves growth under elevated 03 and/or CO2. Bull. Ecol. Soc. Am. (Suppl.) 74, 166.

Brown, K. R. (1991) Carbon dioxide enrichment accelerates the decline in nutrients relative growth rate of Populus tremuloides Michx. seedlings. Tree Physiol. 8, 161-173.

Bunnell, F. L., Tart, D. E. N., Flanagan, P. W. and van Cleve, K. (1977a) Microbial respiration and substrate weight loss. I. Soil Bioi. Biochem. 9, 33-40.

Bunnell, F. L., Tart, D. E. N., Flanagan, P. W. and van Cleve, K. (1977b) Microbial respiration and substrate weight loss. II. Soil Bioi. Biochem. 9,41-47.

Cotrufo, M. F., Ineson, P. and Rowland, A. P. (1994) Decomposition of tree leaf litters grown under elevated CO2: effect of litter quality. Plant and Soi1163, 121-130.

 Couteaûx, M.-M., Mousseau, M., Celerier, M. -L. and Bottner, P. (1991) Increased atmospheric CO2 and litter quality: decomposition of sweet chestnut leaf litter with animal food webs of different complexities. Oikos 61, 54-64.

Cowling, E. B. and Merrill, W. (1966) Nitrogen in wood and its role in wood deterioration. Can. J. Bot. 44, 1539-1554.

Cromack, K., Jr (1973) Litter production and litter decomposition in a mixed hardwood watershed and in a white pine watershed at Coweeta Hydrologic Station, North Carolina. Ph.D. thesis, Univ. Georgia, Athens.

Cromack, K., Jr and Monk, C. D. (1975) Litter production, decomposition, and nutrient cycling in a mixed hardwood watershed and white pine watershed. In: Howell, F. G., Gentry, J. B. and. Smith, M. H. (Eds) Mineral Cycling in Southeastern Ecosystems, pp.609-624. US Energy Research and Development Admin. Symposium Series, CONF- 740613, Washington, DC.

Curtis,P. S., Drake, B. G. and Whigham,D. F.(1989) Nitrogen and carbon dynamics in C3 and C4 estuarine marsh plants growth under elevated CO2 in situ. Oecologia 78,297-301.

Fogel, R., and Cromack, K.Jr(1977) Effects of habitat and substrate quality on Douglas fir litter decomposition in western Oregon. Can. J. Bot. 55, 1632-1640.

Harrison, P. G. and Mann, K. H. (1975) Detritus formation from eel grass (Zostera marina L.): the relative effects of fragmentation, leaching and decay. Limnol. Oceanogr. 20, 924-934.

Hill, H. H. (1926) Decomposition of organic matter in soil. J. Agr. Res. 33, 77-99. IPCC Climatic Change (1992) The Supplementary Report to the IPCC Scientijic Assessment. 1992. Houghton, J. T., Callander, B. A. and Varney, S. K. (Eds) Cambridge University Press, New York.

Johnsen, K. H. (1993) Growth and ecophysiological responses of black spruce seedlings to elevated CO2 under varied water and nutrient additions. Can. J. For. Res. 23, 1033-1042.

Kaushik, N. K. and Hynes, H. B. N. (1971) The fate of dead leaves that fall into streams. Arch. Hydrobiol. 68,465-515.

Kemp, P. R., Waldecker, D., Reynolds, J. F., Virginia, R. A. and Owensby, C. E. (1994) Effects of elevated CO2 and nitrogen fertilization pretreatments on decomposition of tallgrass prairie leaf litter. Plant and Soil. 165: 115-127.

Kohen, E. I., Rouhier, H. and Mousseau, M. (1992) Changes in dry weight and nitrogen partiitioning induced by elevated CO2 depend on soil nutrient availability in sweet chestnut (Castanea sativa Mill.). Ann. Sci. For. 49, 83-90.

Larigauderie, A., Hilbert, D. W. and Oechel, W. C. (1988) Effect of CO2 enrichment and nitrogen availability on resource allocation in a grass, Bromus mollis. Oecologia 77, 544-549.

Lux moore, R. J., O'Neil, E. G. Ells, J. M. and Rogers, H. H. (1986) Nutrient uptake and growth responses of Virginia pine to elevated atmospheric carbon dioxide. J. Environ. Qual. 15, 244-251.

Meentemeyer, V. (1978) Macroclimate and lignin.control of decomposition rates. Ecology 59,465-472.

Melillo, J. M. ( 1983) Will increases in atmospheric concentrations affect litter decay rates? In: The Ecosystems Center Annual Report, pp. 10-11, Marine Biological Laboratory, Woods Hole, Mass.

Melillo, J. M., Aber, J. D. and Muratore, J. F. (1982) Nitrogen and lignin control of hardwood leaf litter decomposition dynamics. Ecology 63, 621-626.

Melillo,J. M.,Naiman, R.J.,Aber,J. D. and Linkins,A. E. (1984) Factors controlling mass loss and nitrogen dynamics of plant litter decaying in northern streams. Bulletin of Marine Science 35(3): 341-355.  

Melillo,J. M., Callaghan, T. V., Woodward, F. I., Salati, E. and Sinha, S. K. (1990) Climate change-effects on ecosystems. In: Boughton, J T., Jenkins, G. J. and Ephraums, J. J. (Eds) Climate Change- The IPCC Scientific Assessment,pp. 282-310. Cambridge Univ. Press.

Monnier, G. and Jeanson, C. (1964) Studies on the stability of soil structure: influence of moulds and soil fauna. In: Ballsworth, B. G. and Crawford, D. V. (Eds) Experimental Pedology, pp. 244-254. Butterworths, London.

Norby, R. J., Pastor, J. and Melillo, J. M. (1986) Carbon-nitrogen interactions in CO2-enriched white oak: physiological and long-term perspectives. Tree Physiol. 2, 233-241.

O'Neil, E. G., Lux moore, R. J. and Norby, R. J. (1987) Elevated atmospheric CO2 effects on seedling growth, nutrient uptake, and rhizosphere bacterial population of Liroden- dron tulipifera. Plant and Soil 104, 3-11.

Overdieck, D. and Reining, E.(1986) Effect of atmospheric CO2 enrichment on perennial ryegrass(Lolium perenne L.) and white clover (Trifolium repens L.) competing in managed model-ecosystems. II. Nutrient uptake. Acta Oecol. Plant. 7, 367-378.

Parton, W. J., Schimel, D. S., Cole C. V. and Ojima, D. S. (1987) Analysis of factors controlling soil organic matter on Great Plains Grasslands. Soil Sci. Soc. Am. J. 51: 1173-1179.

Peterjohn,W. T., Melillo,J. M., Steudler, P. A.,Newkirk, K. M. Bowles, F. P. and Aber, J. D. (1994) Responses of trace gas fluxes and N availability to experimentally elevated soil temperatures. Ecol. Appl. 4, 617-625.

Prescott, C. E., Corbin, J. P. and Parkinson, D. (1989) Biomass, productivity, and nutrient-use efficiency of aboveground vegetation in four Rocky Mountain coniferous forests. Can. J. For. Res. 19,309-317.

Rastetter, E. B., McKane, R. B., Shaver, G. R., Melillo, J. M., Nadelhoffer, K. J., Bobbie, J. E. and Aber, J. D. (1992) Changes in C storage by terrestrial ecosystems: how C-N interactions restrict responses to CO2 and temperature. Water, Air and Soil Pollution 64: 327-344.

Strain, B. R. and Bazzaz, F. A. (1983) Terrestrial Plant Communities. In: E. R. Lemon (Ed.) CO2 and Plants, pp. 177-222. AAAS Selected Symposium. Westview Press, Boulder, Colo.

Taylor, B. R., Parkinson, D. and Parsons, W. F. J. (1989) Nitrogen and lignin content as predictor of litter decay rates: a microcosm test. Ecology 70,97-104.

Tenney, F. G. and Waksman, S. A.(1929) Composition of natural organic materials and their decomposition in the soil: IV. The nature and rapidity of decomposition of the various organic complexes in different plant materials, under aerobic conditions. Soil. Sci. 28, 55-84.

Waksman, s. A. and Gerretsen, F. C. (1931) Influences of temperature and moisture upon the nature and extent of decomposition of plant residues by micro-organisms. Ecology 12, 33-60.

Waksman, S. A. and Tenney, F. G. (1928) Composition of natural organic materials and , their decomposition in the soil: III. The influence of nature of plant upon the rapidity of its decomposition. Soil Sci. 26, 155-171.

Witkamp, M. (1966) Decomposition of leaf litter in relation to environment, microflora and microbial respilation. Ecology 47, 194-201.

 

Back to Table of Contents
 

The electronic version of this publication has been prepared at
the M S Swaminathan Research Foundation, Chennai, India.

 

>

grace_is_by_our_lord  posted on  2009-07-11   17:30:52 ET  Reply   Trace   Private Reply  


#36. To: farmfriend (#33)

Eeeeeek, there ya go again gettin' all sciencey & stuff. That's just not normal for chicky-poos, you must be a witch. I think I'm going to have to burn you at the stake.

Just as soon as I find out if you're carbon-neutral or not.

Regardless, rest assured there's going to be a pole involved, somehow.

Godfrey Smith: Mike, I wouldn't worry. Prosperity is just around the corner.
Mike Flaherty: Yeah, it's been there a long time. I wish I knew which corner.
My Man Godfrey (1936)

Esso  posted on  2009-07-11   17:34:03 ET  Reply   Trace   Private Reply  


#37. To: farmfriend (#33)

Here is three: http://www.faqs.org/abstracts/Earth-sciences/The-effect-of-nutrients-and-enriched-CO2-environments-on-production-of-carbon-based-allelochemicals-.html

grace_is_by_our_lord  posted on  2009-07-11   17:40:30 ET  Reply   Trace   Private Reply  


#38. To: farmfriend (#33)

Here is four: http://cat.inist.fr/?aModele=afficheN&cpsidt=4817685

Titre du document / Document title Influence of elevated atmospheric CO2 concentrations on plant nutrition Auteur(s) / Author(s) CONROY J. P. ; Affiliation(s) du ou des auteurs / Author(s) Affiliation(s) Univ. Western Sydney, fac. horticulture, Richmond N.S.W. 2753, AUSTRALIE Résumé / Abstract The rising levels of atmospheric CO2 are likely to increase biomass production of C3 species in both natural and managed ecosystems because photosynthetic rates will be higher. The greatest absolute increase in productivity will occur when nitrogen and phosphorus availability in the soil is high. Low nitrogen does not preclude a growth response to high CO2, whereas some C3 species fail to respond to high CO2 when phosphorus is low, possibly because insufficient phosphorus is available to maintain maximum photosynthetic activity at high CO2.
C3 plants response to high CO2 because the flux of carbon through the photoreductive cycle is increased and photorespiration is suppressed. This change in metabolism appears to alter the foliar nutrient concentration required to promote maximum productivity (critical concentration) (...)
Revue / Journal Title Australian journal of botany ISSN 0067-1924 CODEN AJBTAP Source / Source 1992, vol. 40, no 4-5 (1 p.1/2), pp. 445-456 Langue / Language Anglais Editeur / Publisher Commonwealth Scientific and Industrial Research Organization, Collingwood, AUSTRALIE (1953) (Revue) Mots-clés anglais / English Keywords Medium enrichment ; Greenhouse effect ; Nutrition ; Biomass ; C3-Type ; Photosynthesis ; Bioavailability ; Carbon cycle ; Review ; Nitrogen ; Phosphorus ; Carbon dioxide ; Nutrient ; Mots-clés français / French Keywords Enrichissement milieu ; Effet serre ; Nutrition ; Biomasse ; Type C3 ; Photosynthèse ; Biodisponibilité ; Cycle carbone ; Article synthèse ; Azote ; Phosphore ; Carbone dioxyde ; Nutriment ; Mots-clés espagnols / Spanish Keywords Enriquecimiento medio ; Efecto invernadero ; Nutrición ; Biomasa ; Tipo C3 ; Fotosíntesis ; Biodisponibilidad ; Ciclo carbono ; Artículo síntesis ; Nitrógeno ; Fósforo ; Carbono dióxido ; Nutriente ; Localisation / Location INIST-CNRS, Cote INIST : 5687 D, 35400003460491.0040

Nº notice refdoc (ud4) : 4817685

grace_is_by_our_lord  posted on  2009-07-11   17:50:24 ET  Reply   Trace   Private Reply  


#39. To: farmfriend (#33)

Here is five: http://www.sciencedaily.com/releases/2002/12/021206075233.htm

Climate Change Surprise: High Carbon Dioxide Levels Can Retard Plant Growth, Study Reveals

ScienceDaily (Dec. 6, 2002) — The prevailing view among scientists is that global climate change may prove beneficial to many farmers and foresters – at least in the short term. The logic is straightforward: Plants need atmospheric carbon dioxide to produce food, and by emitting more CO2 into the air, our cars and factories create new sources of plant nutrition that will cause some crops and trees to grow bigger and faster. But an unprecedented three-year experiment conducted at Stanford University is raising questions about that long-held assumption. Writing in the journal Science, researchers concluded that elevated atmospheric CO2 actually reduces plant growth when combined with other likely consequences of climate change – namely, higher temperatures, increased precipitation or increased nitrogen deposits in the soil. See also: Plants & Animals

* Nature * Endangered Plants * Ecology Research

Earth & Climate

* Global Warming * Climate * Environmental Issues

Reference

* Consensus of scientists regarding global warming * Scientific opinion on climate change * Ocean acidification * Fossil fuel

The results of the study may prompt researchers and policymakers to re-think one of the standard arguments against taking action to prevent global warming: that natural ecosystems will minimize the problem of fossil fuel emissions by transferring large amounts of carbon in the atmosphere to plants and soils.

"Perhaps we won't get as much help with the carbon problem as we thought we could, and we will need to put more emphasis on both managing vegetation and reducing emissions," said Harold A. Mooney, the Paul S. Achilles Professor of Environmental Biology at Stanford and co-author of the Dec. 6 Science study.

He noted that the Stanford study is the first ecosystem-scale experiment to apply four climate change factors across several generations of plants.

"To understand complex ecological systems, the traditional approach of isolating one factor and looking at that response, then extrapolating to the whole system, is often not correct," Mooney said. "On an ecosystem scale, many interacting factors may be involved."

Jasper Ridge Global Change Project

The findings published in Science are among the first results of the Jasper Ridge Global Change Project – a multi-year experiment designed to demonstrate how a typical California grassland ecosystem will respond to future global environmental changes.

Located in a fenced off section of Stanford's 1,189-acre Jasper Ridge Biological Preserve, the novel experiment was designed to simulate environmental conditions that climate experts predict may exist 100 years from now: a doubling of atmospheric CO2; a temperature rise of 2 degrees F; a 50 percent increase in precipitation; and increased nitrogen deposition – largely a byproduct of fossil fuel burning.

Launched in 1997, the Jasper Ridge experiment was conceived by Mooney and Christopher B. Field, a professor by courtesy in Stanford's Department of Biological Sciences and director of the Carnegie Institution's Department of Global Ecology, also located on the Stanford campus.

"Most studies have looked at the effects of CO2 on plants in pots or on very simple ecosystems and concluded that plants are going to grow faster in the future," said Field, co-author of the Science study. "We got exactly the same results when we applied CO2 alone, but when we factored in realistic treatments – warming, changes in nitrogen deposition, changes in precipitation – growth was actually suppressed."

To mimic future climate conditions, Field, Mooney and their colleagues mapped out 36 circular plots of land, each about six feet in diameter. Four plots are virtually untouched, receiving no additional water, nitrogen, carbon dioxide or heat. Each of the remaining 32 circles is divided into four equal quadrants separated by underground partitions to prevent roots in one section from invading neighboring tracts. In these smaller quadrants, researchers study all 16 possible combinations of elevated and normal CO2, heat, water and nitrogen.

The plots thicken

The biggest surprise from the study was the discovery that elevated carbon dioxide only stimulated plant growth when nitrogen, water and temperature were kept at normal levels.

"Based on earlier single-treatment studies with elevated CO2, we initially hypothesized that, with the combination of all four treatments together, the response would be additional growth," said W. Rebecca Shaw, a researcher with the Nature Conservancy of California and lead author of the Science study.

But results from the third year of the experiment revealed a more complex scenario. While treatments involving increased temperature, nitrogen deposition or precipitation – alone or in combination – promoted plant growth, the addition of elevated CO2 consistently dampened those increases.

"The three-factor combination of increased temperature, precipitation and nitrogen deposition produced the largest stimulation [an 84 percent increase], but adding CO2 reduced this to 40 percent," Shaw and her colleagues wrote.

The mean net plant growth for all treatment combinations with elevated CO2 was about 4.9 tons per acre – compared to roughly 5.5 tons per acre for all treatment combinations in which CO2 levels were kept normal. However, when higher amounts of CO2 gas were added to plots with normal temperature, moisture and nitrogen levels, aboveground plant growth increased by nearly a third.

Why would elevated CO2 in combination with other factors have a suppressive effect on plant growth? The researchers aren't sure, but one possibility is that excess carbon in the soil is allowing microbes to outcompete plants for one or more limiting nutrients.

"By applying all four treatments, we may be repositioning the ecosystem so that another environmental factor becomes limiting to growth," Field observed. "For example, by increasing plant growth as a result of adding water or nitrogen, the ecosystem may become more sensitive to limitation by another mineral nutrient such as phosphorous, potassium or something else we hadn't been measuring."

A new five-year experiment is underway at the Jasper Ridge site to analyze potential limiting nutrients in the soil along with microbial-plant interactions and the molecular biology of the vegetation.

Policy implications

Field and his colleagues say that their ultimate goal is to use the results of the Jasper Ridge study to forecast what will happen to other ecosystems – from alpine tundra to tropical rainforests.

"In the past, people have argued that perhaps we don't really need to worry about fossil fuel emissions, because increased plant growth will effectively pull elevated CO2 concentrations out of the atmosphere and keep the world at the appropriate equilibrium," he added. "But our experiment shows that we can't count on the natural world, the unmanaged world, to save us by pulling down all the atmospheric CO2."

Added Mooney: "Our study demonstrates that there is still a lot to learn about the factors that regulate global climate change. But we also know a lot already, more than enough to engage in a serious discussion about action to reduce CO2 emissions from burning fossil fuels and clearing forests."

###

Other coauthors of the Science study are former Stanford doctoral student Erika S. Zavaleta, now a Nature Conservancy post-doctoral fellow at the University of California-Berkeley; Nona R. Chiariello, research coordinator of Stanford's Jasper Ridge Biological Preserve; and Elsa E. Cleland, a graduate student in the Stanford Department of Biological Sciences.

The study was supported by the National Science Foundation, the Morgan Family Foundation, the David and Lucile Packard Foundation, the Jasper Ridge Biological Preserve, the Carnegie Institution of Washington, the U.S. Department of Energy, the U.S. Environmental Protection Agency, the Switzer Foundation and the A.W. Mellon Foundation.

grace_is_by_our_lord  posted on  2009-07-11   17:54:57 ET  Reply   Trace   Private Reply  


#40. To: farmfriend (#33)

So I can go on and on and on. It is an established fact increased ambient or environmental CO2 has little to do with actual increased nutrients based upon actual agricultural production. The plants are actually destroyed by the poor environments. To change things requires HUGE amounts of added plant nutrients such as potassium in the soil.

Your turn.

grace_is_by_our_lord  posted on  2009-07-11   17:59:59 ET  Reply   Trace   Private Reply  



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