Bart,
Thanks. This is a topic that has turned into a political football. The best science is going to be obscured by the timber lobby propaganda mill. Bob ----- Original Message ----- From: "Bart Bouricius" <[email protected]> To: [email protected] Sent: Friday, January 1, 2010 12:17:33 PM GMT -05:00 US/Canada Eastern Subject: Re: [ENTS] Fwd: carbon storage Hi Bob and all, This is my first attempt to enter the dialog because I know a little about this subject. A friend of mine, Richard Houghton who is the director of the Woods Hole Research Center has spent many years examining Carbon flux (movement of Carbon in various forms into and out of the atmosphere, the soil and groundwater) and was the first scientist to use remote sensing to get a rough measurement of how much CO2 was being emitted into the atmosphere as a result of burning the Amazonian forests in Brazil in the 1980's. He noted that you generally loose more CO2 from the soil than from the trees after a fire and certainly after a clear cut. It is never a simple calculation, and when a question such as how much carbon is stored in late succession or old growth forest the answer, of course, is always it depends . I know we are looking for a simple average, but often our question confounds the average answer. In areas where clear cutting or large scale natural or human induced burning does not occur succession occurs in a light gap resulting from a large tree fall and is quite variable. I assume of course that we are looking at the Eastern United States and even so, the soils are so different that we would have to get many different measurements to get an even rough approximation. Nevertheless, with clear definitions of what we are talking about and the range of possibilities that this includes, we might come up with something useful, as I am certain that some of this has been measured. I will approach Richard on this and see what references he has. Possibly Lee is already aware of the necessary references and has a good answer. My suspicion is that older forest on average will have deeper soils, assuming all else is equal, because of inherent characteristics and because they are generally farther away from introduced earth worms and plants that might impact the soil depth negatively. For this reason I would predict and hope that the soil factor may be quite significant in calculating carbon storage and that old growth would store quite a bit more, but we can't let our hopes influence the actual facts or we loose all credibility. Bart Bouricius On Fri, Jan 1, 2010 at 11:20 AM, Bob < [email protected] > wrote: Lee Thanks. The complexity of carbon sequestration belies the simplistic view taken by the timber lobby. Bob Sent from my iPhone On Jan 1, 2010, at 10:57 AM, Lee Frelich < [email protected] > wrote: > Bob: > > I think they basically got the story correct: > 1. Old growth forests continue to soak up carbon for much longer > than we > used to think > 2. However, they do not soak up carbon as fast as young-middle aged > forests > 3. Old growth forests store a huge amount of carbon per acre, > especially > in soil, and if harvested some of that will continue to leak out of > the > soil for some time, thus negating the sequestration that occurs by the > new growth. > > Another point is that a substantial amount of carbon is emitted by > cutting down a tree, hauling it to the mill, making it into lumber, > and > then transporting the lumber to a lumber yard and to a construction > site. This can vary from 25% to 100%+ of the amount of carbon in the > wood, depending on harvest methods and distance to the mill and to the > site where the wood is ultimately used, and type of transportation > used. The benefit of storing carbon in wood products is not as > great as > some people would have us believe. However, making steel and concrete > also emits a lot of CO2, so that using wood as a building material may > under some circumstances lead to less total emissions relative to > other > building materials (given that a building was going to be built > anyway). > In the future steel and cement plants may be able to sequester the CO2 > coming from their smokestacks, which would throw the balance back in > favor of steel and concrete. > > Lee > > > Bob wrote: >> Lee >> >> Are you up on the research identified below, and if so, any >> thoughts you'd be willing to share? >> >> Bob >> >> Sent from my iPhone >> >> Begin forwarded message: >> >>> *From:* Mike Ryan < [email protected] <mailto: [email protected] >>> >> >>> *Date:* December 31, 2009 12:03:44 PM EST >>> *To:* [email protected] >>> <mailto: [email protected] >, >>> [email protected] >>> <mailto: [email protected] >>> > >>> *Cc:* Bob Leverett < [email protected] >>> <mailto: [email protected] >> >>> *Subject:* *Re: carbon storage* >>> >>> *Re: Science or conventional 'wisdom' from people who cut down trees >>> for a living?**:* >>> >>> "...findings lay to rest the hoary notion that old-growth forests >>> are worthless in the fight against global warming. On the contrary, >>> they are an essential part of the struggle." >>> >>> "Plants take in CO2 and harness the energy of the sun to drive the >>> chemical reaction that melds carbon with water, producing the >>> substance of stem and leaf and releasing oxygen. When darkness or >>> drought bring this process of photosynthesis to a halt, plants >>> respire, just as humans do. That is, plants breathe in oxygen and >>> exhale CO2. *But over the long life span of trees in an undisturbed >>> forest, huge reservoirs of carbon are stored for great stretches of >>> time in the organic matter in soil as well as in living wood.*** >>> >>> *People who cut down trees for a living tend to measure their value >>> in dollars and cents. Traditionally, the timber industry has seen >>> mature forests, with massive trees left standing and big logs >>> rotting >>> on the ground, as examples of waste; replanted clear-cuts, by >>> contrast, represent an ideal of economic productivity.* Now global >>> warming has forced foresters to address the impact of logging on the >>> flow of carbon between forests and the atmosphere, and *many in the >>> industry have insisted that stands of young, fast-growing trees >>> capture carbon more efficiently than do older forests.* Using a >>> recently developed technology called the eddy covariance method-more >>> commonly known as eddy flux ; Law and her colleagues are showing >>> that >>> *those assumptions are wrong.* >>> >>> It turns out that forests hundreds of years old can continue to >>> actively absorb carbon, holding great quantities in storage. >>> *Resprouting clear-cuts, on the other hand, often emit carbon for >>> years,* despite the rapid growth rate of young trees. This is >>> because >>> decomposer microbes in the forest soil, which release CO2 as they >>> break down dead branches and roots, work more quickly after a stand >>> is logged. *On the dry eastern face of the Cascades, for example, >>> where trees grow slowly, a replanted clear-cut gives off more CO2 >>> than it absorbs for as much as 20 years.* "That's a long time," Law >>> observes, "during which microbes respiring in the soil, rather than >>> trees photosynthesizing aboveground, dominate the carbon balance." >>> >>> Eddy flux measurement is one of Law's most crucial tools, enabling >>> her to track the exchange of CO2 and water vapor between forest and >>> air over large swaths of landscape, and at a level of detail that's >>> never before been possible. The automated gas analyzers mounted on >>> the eddy flux tower we're standing on measure CO2 concentrations 20 >>> times per second. Meanwhile a sonic anemometer, a three-pronged >>> device that resembles a robotic claw, tracks wind speed and >>> direction. The combination of these two data sets reveals the >>> shifting flow of carbon in and out of a forest, day or night, winter >>> or summer. Law notes with pride that all the technology at this >>> research site is powered by photovoltaic panels. >>> >>> Other tools provide Law with additional insights into the flow of >>> carbon through the intricate pathways of the forest. To photograph >>> root growth, she slides a remote-controlled camera into a clear tube >>> sunk belowground at a tree's base. Set on the forest floor are >>> instrument-laden cylinders that hum to life every five minutes, >>> lower >>> themselves like miniature flying saucers, settle onto a patch of >>> earth, and *record the amount of carbon coming out of the soil.*** >>> >>> Law's data show that this 90-year-old forest is, in fact, at the >>> peak >>> of its ability to absorb carbon. The uptake of carbon by ponderosa >>> pines increases gradually, then reaches a plateau at some point >>> between 50 years and 90 years. Once this plateau is reached, the >>> trees and the soil will together continue to form a rich bank of >>> stored carbon that cannot be equaled by any newly sprouted stand. >>> During her work in California and the Pacific Northwest, *she's >>> found >>> forests as old as 800 years that continue to absorb more carbon than >>> they release.* >>> >>> Across forest types globally," Law says, "we find that the amount of >>> carbon stored is high in older forests, and that live carbon [the >>> carbon in living wood] continues to accumulate for centuries." >>> AmeriFlux's findings are now publicly available online, and climate >>> modelers are beginning to use the data to forecast the ways forest >>> growth-or forest loss-could affect climate. Such models are used in >>> simulations by the Intergovernmental Panel on Climate Change, whose >>> authoritative reports shape climate policies worldwide. >>> >>> *But these findings are news to the foresters I know. All of them >>> remember, from college textbooks, a graph of tree growth that shows >>> young trees bulking up rapidly over the first few decades of their >>> lives, reaching a peak at 60 years to 70 years. After that, growth >>> rates drop off. This pattern, which indicates that the most >>> profitable point at which to harvest timber comes before the trees >>> reach a century of growth, is deeply ingrained forestry >>> wisdom...ignores the importance of the large amounts of carbon held >>> in the living wood and fertile soil of old forests. When such stands >>> are cut, about a third of the carbon is captured in marketable >>> timber; the rest is rapidly released into the atmosphere. Like most >>> foresters, Keye appears unaware of recent studies by Law, Wofsy, and >>> their colleagues. Eddy flux measurement, supplemented by careful >>> accounting of the carbon absorbed and released from leaves, the live >>> roots burgeoning beneath the soil, and the rotting detritus of the >>> forest floor, reflects the life of forests in far greater detail >>> than >>> traditional forestry analyses, which are based on measuring only >>> those trees that are large enough to produce marketable timber.* >>> >>> Source: Natural Resources Defense Council, 2008; Sharon Levy, 'The >>> Giving Trees' >>> >>>> ----- Original Message ----- >>>> *From:* Charlie Thompson <mailto: [email protected] > >>>> *To:* [email protected] >>>> <mailto: [email protected] >>>> > >>>> *Sent:* Wednesday, December 30, 2009 3:47 PM >>>> *Subject:* Re: carbon storage >>>> >>>> To answer, I need answers to these questions: >>>> >>>> 1) What general forest type? >>>> 2) Does "stored" include all carbon pools? >>>> [The answer to the general forest type question will provide the >>>> age/ stage brackets for defining "late successional" and >>>> "old-growth".] >>>> >>>> Charlie >>>> >>>> On Dec 30, 2009, at 1:05 PM, Bill Logue wrote: >>>> >>>>> Fred Heyes has asked if anyone knows the answers to the >>>>> questions below: >>>>> “Can someone tell me with reasonable accuracy >>>>> how much carbon is stored per year per acre in late >>>>> successional >>>>> how much carbon is stored per year per acre in old growth >>>>> forests” >>>>> >>>>> -- >>>>> >>> >> -- >> Eastern Native Tree Society http://www.nativetreesociety.org >> Send email to [email protected] >> Visit this group at http://groups.google.com/group/entstrees?hl=en >> To unsubscribe send email to [email protected] > > -- > Eastern Native Tree Society http://www.nativetreesociety.org > Send email to [email protected] > Visit this group at http://groups.google.com/group/entstrees?hl=en > To unsubscribe send email to [email protected] -- Eastern Native Tree Society http://www.nativetreesociety.org Send email to [email protected] Visit this group at http://groups.google.com/group/entstrees?hl=en To unsubscribe send email to [email protected] -- Eastern Native Tree Society http://www.nativetreesociety.org Send email to [email protected] Visit this group at http://groups.google.com/group/entstrees?hl=en To unsubscribe send email to [email protected] -- Eastern Native Tree Society http://www.nativetreesociety.org Send email to [email protected] Visit this group at http://groups.google.com/group/entstrees?hl=en To unsubscribe send email to [email protected]
