That’s the rate that people are releasing carbon to the atmosphere from fossil fuel combustion and deforestation today. I know, it’s apples and oranges; carbon in the form of oil is more immediately toxic to the environment than it is as CO2 (although CO2 may be more damaging on geologic time scales). But think of it — five thousand spills like in the Gulf of Mexico, all going at once, each releasing 40,000 barrels a day, every day for decades and centuries on end. We are burning a lot of carbon!
I found this follow-on link (I accessed it through the biochar.org link given above) quite interesting:
http://www.house.gov/smbiz/hearings/hearing-5-21-09-biofuels-regulations/Das.pdf
In it, Dr. K.C. Das, of the University of Georgia, tells Congress ever-so-politely that they really need to revisit the existing biofuels legislation in order to mitigate unintended consequences currently holding back various promising lines of research. It’s evident that Prof. Das is operating with a practical knowledge and appreciation of American agriculture as it actually exists today, as well as the scientific background that one would naturally expect.
#148 David Horton,
Well I, and many many ecologists and botanists would disagree with you. I have read most of the page on fire on your website and I agree with some points but disagree with many others. However I note that there is not a single reference to refereed publications. Until you provide suitable references which have gone through the process of peer review, I think it is reasonable to treat it in the same way as any other unrefereed opinion piece.
There is ample literature of the effects of fire on many plants.
For a start I would agree that not many plants actually require fire though there are some. For example there are a few pyrogenic flowering species; most are monocots but there are a few dicots (1).
There are other types of dependence too. “Banksia hookeriana is a highly nonsprouting serotenous shrub restricted to the fire prone northern sandplain scrub-heaths of Western Australia.” The seeds are maintained in tightly closed pods as an arial seed bank. Seeds accummulate up to a maximum after about 15 years. There are losses to insects, decay and spontaneous opening, but essentially all the fertile seeds are maintained in the closed pods. Fire triggers the release of most or all of the seeds a short time afterwards, and the seed germinates in the next growing season. (5)
Another example is Banksia cuneata, which “is a large florierous shrub or tree confined to seven small populations in southwestern Western Australia, The stand at the study site consisted of groups of even aged, fre sensitive plants, suggesting recruitment is usually dependent on recurrent fire.”(3) Again seeds accumulated and were maintained as an arial seed bank for 19 years of the study site. While there were small losses due to prefire release there were no plants produced from these. However “most of the 17,100 viable canopy stored seeds were released within 24 hours of a hot autumn fire, whereas wet dry cycles were required following milder fires.”(3)
I’d say, (and the authors consider) that the species are dependent upon fire to a large extent. Note that at least Banksia Cuneata is fire sensitive so it burns and doesn’t survive. However its seeds are spread on empty ground where they are likely to have a higher chance of growing and so the parent tree is likely to have better reproductive success.
There is also much indirect evidence that fire plays a major part in ecological communities. For example “a world without fire had very different vegetation zones compared with the actual vegetation geography.” In their modelling for example, Navjot et al (4) state “when fire was ‘switched off’, dense tree cover increased from 27% to 56% of the vegetated Earth surface and more than half (52%) of the current global distribution of tropical savannas were transformed to angiosperm-dominated forests.” (5) and “recurrent disturbance plays an important role in maintaining a tree-grass balance (6). Given the high flammability of savannahs, it seems that disturbance due to fire is particular importance.”
Clearly without fire, certain types of plant could become scarce to extinct in some environments, crowded out by other species. Under those circumstances it is not unreasonable to suggest that certain species are dependent upon fire for survival.
I can think of several reasons. If a tree can make its foliage and surrounding vegetation burn more fiercely, there is likely to be less competition for its offspring and hence give them a better chance of survival and a higher reproductive success for the parent. If the tree can survive even better. After all, reproductive success is what it is all about, not necessarily survival of the tree itself.
Such a scenario has been suggested before. Mutch has suggested that “Plant species which have survived fires for tens of thousands of years may not only have selected survival mechanisms, but also inherent flammable properties that contribute to the perpetuation of fire-dependent plant communities.” (7)
Fire may also be important and advantageous for fauna too (8).
For a more comprehensive review with references try (9)
etc etc. There are so many published studies in a similar vein that I am surprised that you are making such generalized statements about fire and plants. I am sure there are situations where fire is not so important but they are likely to be very regional.
In answer to your specific points.
as above, it may be if it increases reproductive success.
many do and many have deeply buried epicormal buds which survive fire (and what other advantage would they provide _ though this is not an argument I would persue.)
What evidence is there for that. In fact the Banksia species I noted above retained almost all the viable seeds through 19 years of average rainfall (1970s to 1980s), yet opened within 24 hours of a fire.
inadvertently it may not be a good thing, but if you have evolved to open after a fire then it would be the best thing to do.
That may be true but there was not much paper or straw in forests millenia ago. Plus smoke is smoke and still indicates a fire close by.
Perhaps fire is also important for some forest plants in those other countries too.
I agree they certainly affect herbiverous fauna but what evidence do you have that the increased fire intensity is not advantageous to the plant’s reproductive success.
Depends upon what you mean by fertility. Charcoal certainly helps water retention and probably retention of many ionic compounds, which in turn is likely to help plants to prosper.
Fire certainly removes organic matter. However in every bush fire I have ever walked around (several hundred), even in the most intense ones, there has always been lumps of partly burnt timber, charcoal etc. In the normal situation I am sure this would have been cycled into the soil; eg by burrowing insects or other fauna. Each fire might not produce much but over the millenia it would have built up to the sort of levels seen even now in undisturbed areas of native vegetation. Skjemstad et al (10) found that up to 30% of soil carbon, or 0.8 % by weight of soil is charcoal in a series of samples of Australian soils.
(1) Andrew J. Denham and Tony D. Auld “Flowering, seed dispersal, seed predation and seedling recruitment in two pyrogenic flowering resprouters” Australian Journal of Botany 50(5) 545 – 557.
(2) Enright, N.J., Lamont, B.B. and R. Marsula, (1996) “Canopy seed bank dynamics and optimum fire regime for the highly serotinous shrub, Banksia hookeriana”, J. of Ecology, 84, 9-17
(3) Lamont, B. B., Connell S.W., and Bergl S.M., (1991) “Seed Bank and population dynamics of Banksia cuneata: The role of time, fire, and moisture”, Bot. Gaz. 152, 114-122.
(4) Navjot S. Sodhi, Paul R. Ehrlich, “Conservation Biology for All”, Oxford University Press, 2010.
(5) Bond, W.J., Woodward, F.I. & Midgley, G.F. (2005) The global distribution of ecosystems in a world without fire. New Phytologist 165: 525-538.
(6) Sankaran M., Hanan, N. P., and Scholes, R.J. 2005 “Determinants of woody cover in african savannas” Nature, 438, 846-849.
(7) RW Mutch, “Wildland fires and ecosystems–a hypothesis”, Ecology, 1970.
(8) R. J. Taylor, “Plants, fungi and bettongs: A fire-dependent co-evolutionary relationship”, Austral. Ecology Vol. 16 Issue 3, Pages 409 – 411
(9) N.D. Burrows, “Linking fire ecology and fire management in south-west Australian forest landscapes”, Forest Ecology and Management
Volume 255, Issue 7, 20 April 2008, Pages 2394-2406
(10) Skjemstad,J.O., P. Clarke, J.A. Taylor, J.M. Oades and S.G. Mcclure “The chemistry and nature of protected carbon in soil”,Australian Journal of Soil Research 34(2) 251 – 271
[Response: Thanks Andrew, nice summary. If I get time (unlikely) I’ll add some to it.–Jim]
Andrew, Jim – We are inadvertently heading way OT, and I don’t want to extend this much further unless you want to set up a new post on forests and fires and climate change or something. I am familiar with the literature over many years, and have contributed to it. I do try to avoid talking baloney Jim, and you might be surprised to learn that there are many plant ecologists that agree with me (there is a division between the “fire manager”/”fire ecologist” group and actual ecologists I find).
This whole business began in Australia with a mistaken view of the use of fire by Aborigines and the effects that fire had on the prehistoric landscape. From that basis – assuming that fire had been used extensively, and had modified the landscape – people began looking for the “adaptations to fire” that they were sure must be there.
Whether you think that a couple of species of Banksia with slow opening pods are evidence that Australian flora is adapted to fire and needs to be burnt regularly (the corollary that flows from this for fire managers) or that the vast numbers of species that can’t survive frequent fires are evidence against seems to depend on the preconceptions you see the data with.
Just to pick up on a couple of Andrew’s points. The business about smoke. The original contention was that the effect was due to something unique in burning Eucalyptus and uniquely applied to some Australian species. If those things had been true you might well work out how this adaptation had occurred. When I first saw these experiments I was convinced that maybe here was a unique piece of evidence for fire adaptation. However the experiments continued, and the effect (a) has nothing to do with smoke from Australian plants with some unique ingredient, but can result from any kind of burnt vegetable matter and (b) the effect isn’t just on Australian plants but on pretty much every plant that it has been tried on, no matter what their evolutionary history from whatever part of the world they originated. Whatever is going on here in terms of plant physiology it has nothing to do with adaptation of Australian plants to fire.
This thick bark business is puzzling. Large numbers of Eucalypts shed their very thin bark seasonally. They can all however recover with shoots from trunk or leaves after drought has caused the tops to die back, or when they are damaged by fire (as long as the damage isn’t too severe). Being able to recover after a setback is a general survival mechanism, not a fire adaptation.
I still don’t understand the charcoal business. It is mainly valuable in soil structure and aeration. I guess it does break down over time, but very slowly, and you would be far better off with the organic matter in the soil that hadn’t been carbonified (if that’s a word). In addition when the fire sterilises the top layers of soil it is killing the very organisms that break down organic matter. The removal of leaf litter also lets the soil dry out which also reduces decay rates.
Are the oils in pine trees an adaptation to fire? How exactly could you evolve such an adaptation?
Jim, you might bear in mind that I’m not an idiot. I’ve been thinking about and studying this for a long time. The prescribed burning regimes (as well as the practice of thinning) in Australia have serious consequences for the ability of forests to survive at all, let alone survive climate change. I make no apology for continuing to question the basis for the procedure, it has feet of clay.
[Response: I didn’t say you were an idiot, I said you had serious misconceptions. If these were only related to the fire adaptations of Australian plants that would be one thing, but your larger, nonsensical objection to the use of controlled burning is extremely misguided and dangerous. Climate change makes thinning and/or controlled burning only that much more necessary than it already was. You seem to believe it’s necessary to discount the role of past vegetation management practices in order to bolster the argument that climate change is 100% responsible for increased fire damage/risk. This is neither correct nor necessary.–Jim]
Jim. I Would second David’s request for a specific post on this topic.
This has to be one of the most enthralling and scientific debate that I have witnessed ever in blog land! OK, I don’t get out much. :)As regards to natives using fire before us Europeans descents arrived, I will try to find my archive on this subject.
[Response:Thanks, I’m glad it was interesting to you. I’ve been planning a couple of posts on the relationship between climate, fire, and land management for a while. It’s strictly a question of time availability.–Jim
Again, thanx to all who have posted here, real good stuff!
David
Just a few points I would like to make.
1. I make no claims about whether the original Australian inhabitants practiced firestick farming. I do not have sufficient knowledge to discuss this in any sort of depth. However this is probably largely irrelevant to whether Australian plants are fire adapted since it is likely to have been important only over the last 40,000 years at the very most and probably much, much less if at all. It may of course have had an effect on the species composition of many environments if it occured at all.
2. I am also bemused by the assumption that fire adaptation means that fires must be very frequent. There are many studies which show that frequent fires are also detrimental to many fire adapted species. The sort of fire frequency that is generally considered as reasonable from experimental results even for fire adapted species suggests intervals of 10 to 40 year between fires.
2. With regard to fire adaptation. I mentioned a few species which exemplified specific adaptations to fire In fact there are many species with similar structures and with apparently similar life histories, and it seems reasonable to conclude that those adaptations in other species are likely to be, at least in part, adaptations to fire also, until proven otherwise.
3. The types of fire adaptation are quite diverse and can be quite subtle. For example there are many specific instances all over Australia where fire produces effects such as synchronized flowering and seed production.(1, 2) In one instance fire causes mass reproduction in Eucalyptus delegatensis (Mountain Ash), which seems to be a strategy to reduce seed predation by ants, with the result that fires greatly enhance the reproductive success of the parent tree (even though it is a fire sensitive species)(3). I would call that fire adapted.
Another major factor in many eucalypt forests seems to be the ability of eucalypts to chemically suppress germination and establishment of many species in unburnt forest. Seeding, germination and successful establishment predominantly only occurs after fire, due to reduced competition and altered microenvironment which could well include combustion of inhibitory chemicals in the forest litter. I would also call that fire adaptation.(4, 5)
So with all the published work showing specific instances of direct and circumstantial evidence for fire adaptation, then it seems to me that if you want to insist that most Australian flora is not fire adapted then you are going to have to show that such adaptations do not enhance the reproductive success of those plants.
However as you said, this is getting way off topic and so I will say no more.
<1) Gill, A.M. (review) (1981) "Adaptive responses of Australian vascular plant species to fires" in Gill, A.M., Groves, R.H. and Noble I.R. (eds) 'Fire and the Australian biota' Aust Acad Sci: Canberra.
(2) Gill, A.M. (review) (1981) “Coping with fire”, in Pate J.S. and McComb A.J. (eds) The biology of Australian plants (UWA press).
(3) O’Dowd, D.J. and A. M. Gill, “Predator satiation and site alteration following fire: Mass reproduction of Alpine Ash (Eucalyptus delegatensis) in southeastern Australia”, Ecology, 1984, 1052-1066.
(4) Wellington A.B. and Noble, I.R. (1985) “Post fire recruitment and mortality in a population of the mallee Eucalyptus incrassata in semi-arid south eastern Australia”, Journal of Ecology, 73, 645-656.
(5) Bell, D.J. and Williams J.E. (review) (1997) “Eucalypt ecophysiology”, in Williams E. and Woinarski J. “Eucalypt ecology: individuals to ecosystems”, University of Cambridge press.
I think the topic of this thread is scale.
And the scale of the climate change problem is something many people don’t understand..
So i found this interesting talk online today on scale and climate change.
Roger Revelle Centennial Symposium: Powering the Planet
http://www.youtube.com/watch?v=f1sYmBX7rNA&feature=player_embedded#!
Sorry to have lost the thread, which is becoming quite interesting. Jim (Bouldin?)- if you email me at mike.greenframe@gmail.com I can refer you to some of the relevant studies.
In my opinion, Jim, you hold two common opinions that make great intuitive sense, but are not supported by data. One is that wood product “carbon storage” actually means something. No. I repeat: after industrial logging, about 15-20% of the carbon in the onsite vegetation that is harvested or disturbed ends up in wood products, and replaces wood products that have already decayed. This means we’re going around in circles when it comes to sequestration, with a small amount at that.
[Response: ??? I’ve said nothing one way or the other on that topic.]
I’ll also repeat the statement that about 20% of the carbon on a site is released to the atmosphere during and after a fire, and, as you know, a variety of fire dependent species (including insect predators) are able to develop habitat.
As for thinning, this is a complex and controversial subject, obviously. It’s true of course that many Western forests are overgrown, due to warming, and, especially, human site alterations with regard to species mix and size. Older forests tend to not be overgrown, because the large trees outcompete others and hog the sunlight, resulting in less flammable understory.
One could make a case for thinning in, say, overgrown pine habitat in the PNW Cascade Range, but not in the coastal forests, or even in most of the Sierras. Weurthner thinks it’s useless even in the drier forests of the Northern Rockies.
In the real world, what usually happens with thinning is that “foresters”- who are not biologists- are given the task of making it economical. That means removing the large trees, which is much worse than doing nothing.
Again, check out the work of Hansen, Harmon, Franklin, and Weurther on this subject.
And I repeat my request for input from carbon scientists whose work I have come to know and respect. Forest carbon science is a rarified field, and only a few have true expertise here.
[Response: I am familiar with the work of all of them. There are many folks working on the carbon cycle and on fire, including a couple of us here. I find a number of your statements to be either wrong or questionable, based on knowledge of the literature and on my own research program, which focuses directly on forest change and land management, and now, climate. I don’t base my judgments and statements on intuition, believe me. There will be posts on these topics when the time and energy avails.–Jim]
Thanks for sharing your expertise here, Jim. We have a few areas of disagreement, but Realclimate needs a post devoted strictly to the forest carbon cycle, written by someone better qualified than I. The best person to write it is the man many consider to be the guru on the subject, Dr. Harmon of Oregon State. Your UC Davis colleague Chad Hansen could perhaps write a separate post on fire.
Are you amenable to this suggestion? Alternatively, if you write this post, please give me some notice and I will alert forest carbon scientists of my acquaintance to weigh in- including Franklin of UW, Heath of USFS, and Shulte of Planck.
This whole subject is badly neglected on all of the climate blogs, and is not well addressed by IPCC, either- due to timber industry bullying of the relevant committees, over sideshows like HWP accounting and leakage. The main thing we need to do is deforest less, and stop considering various industry “treatments” as having any value. This seems to be an area of disagreement between us as well.
[Response: The “main thing” we need to do is to get the science right, regardless of who wants what to be the case.–Jim]
This issue came up several years ago when somebody commented that old-growth forests no longer add carbon. At the time posters seemed to think trees stop growing. So I questioned the reasons why people believe a mature forest cannot add carbon. It quickly became apparent that the reason is not science; it’s a management choice, one of which is the management choice to do nothing to the forest ever again.
To say the forest management has failed in the past is not a scientific argument. I don’t dispute that forest management has failed and have no doubt that the science shows that failure, but does the science also say forest management cannot work? I rather doubt that. What forest strategy will create the largest carbon storage?
159: JCH said about forest management:
You might be interested in reading Stewart Brand’s book “Whole Earth Discipline: An Ecopragmatist Manifesto”. Towards the end he claimed that prior to 1492 the American Indians managed North America. I have no idea whether that is a reasonable claim, but it was an interesting read. He should have had an editor with a big red pen force him to thin it down about 50 pages.
John E. Pearson (160) — Also read “ancient Forests”. There is little doubt that some Amerinidans practiced a form of (mild) forest management.
I think 2 or 3 (?) years ago, in an issue of “National Geographic”, it was stated that earthworms (or at least the familiar kind?) had been wiped out (naturally) in North America before Europeans came, and the new species caused a significant change in … leaf litter, as I recall reading. (PS I wonder what Robins ate before this?)
Patrick – there have alway been earthworms in N America – there are some who say some of the 1/3 or so of types that are “invasive” are a problem with consuming detritus in northern forests. Earthworms also contribute significantly to agricultural soil health fertility.
161 David Benson said: read “Ancient Forests”
Who’s the author? I found several books with “Ancient Forests” in the title at amazon but none with that exact title.
I wouldn’t think “old growth” is necessarily carbon neutral. If the conditions were constant we would expect longterm equilibrium. But climate, atmospheric chemistry, and the balance of species are changing, primarily as a result of anthropomorphic effects. So the carbon storage in the future “equilibrium” state is not likely to be the same as it was in preindustrial times. Also we have some forests whose detritus accumulates in the form of peat or organic matter in permafrost. These forests are obviously sequestering carbon in the soil/swamp/permafrost.
According to http://www.nrri.umn.edu/worms/forest/index.html
“Native earthworm species have never been documented in most of the Great Lakes region of North America. Any native North American species of earthworms (in the family Megascolecidae) that may have been living in the region were extirpated when glacial ice sheets covered the Upper Midwest 11,000 to 14,000 years ago, leaving the glaciated areas of North America worm free.”
the extensive glaciated areas of N America were worm free, and human activities have introduced exotic worms.
“Lacking a powerful detrivore such as earthworms, decomposition of the annual leaf litter in earthworm-free hardwood forests is controlled by fungi and bacteria. In this situation, decomposition is slower than accumulation of new litter and the result is the formation of a thick, spongy forest floor, often called a “duff layer”.
The introduction of worms has therefore resulted in a transient reduction of carbon stored in wooded areas of N America that were previously worm free.
I wonder if the growth of new forest/prairie ecosystems as glaciers retreated caused a transient drawdown of CO2 which contributed to the Younger Dryas cooling event?
Re 163 flxible, 166 Brian Dodge – thanks.
The oil spill is nothing to laugh at but I just saw a kid wearing a t-shirt that cracked me up. BP – We’re bring oil to America’s shores. I died laughing because BP’s billion dollar image change to their new sunflower logo is forever going to be associated with the worst environmental disaster to strike America. Check out the shirt here – http://bit.ly/bJAuTb
Sorry guys, bad comparison or analogy in my opinion. This spill is VERY bad and for now more serious than AGW.
Against expectations, world CO2 emission not even down in crisis year 2009: growth China, India nullifies decrease OECD: http://bit.ly/CO209
http://www.ssireview.org/articles/entry/qa_jeffrey_sachs/
Jacob Mack @ 169:
FOR NOW, yes. But the bigger take-away should be that drilling ever harder to reach fields brings with it ever greater risks.
Sooner or later we were going to experience one of them …
http://thedailybite.wordpress.com/2010/04/20/mysterious-gray-whale-deaths-in-puget-sound-bet-peter-watts-has-a-hypothesis/
“… I wonder if the reason for the sparse pickings in the waters off the Alaskan coast last year could be related to findings about the effects of offshore drilling upon marine life that resulted in a professor being purged from the University of Alaska?
Research into what is causing sharp reductions in marine mammal populations that feed in Alaska can be dangerous to a scientific career, as another scientist, Dr. Peter Watts, explains in the blogginheads.tv interview below. (Actually it is only dangerous if you think science is about telling the truth. That is why Dr. Watts decided to write honest fiction instead.)…”
The Feel-Good Spill of the Decade
It begins:
“Dead zones suffocating 20,000 square kilometers of ocean. Endangered wetlands, disappearing at the rate of over 300 Ha/day. Clouds of black viscous poison soiling the coastlines of four states.
And then the Deepwater Horizon blew up.
What, you thought those apocalyptic descriptions were of the spill? You thought the Gulf of Mexico was some pristine marine wilderness before those nefarious assholes from BP came along and ruined everything?
What are you, twelve?
Everything I’ve just described was old news long before April 20….”
On the topic of carbon sequestration in forests, some of you may be interested in an article in the June issue of BAMBOO, The Magazine of the American Bamboo Society:
Bamboo as Carbon-Sink, by Dr. Walter Liese, Department of Wood Biology, University Hamburg. My mother and I edit the magazine, so I can send a copy (pdf) or link to anyone who contacts me at donshor@gmail.com.
Hank – taking the virtual tour along the Gulf of Mexico from Corpus Christi to Mobile, the most common plant one will see:
the chemical plant
The Gulf of Mexico is a chemical cesspool, and not many residents give a flip. It’s the economy. When I moved to Texas in 1980 the Kemp Ridley was already threatened – by shrimp eaters.
I sincerely pray that BP are able to completely stop the spill as soon as possible. The severe weather we’ve been having recently have not helped either.