Carbon sequestration is an excessively expensive and probably technically impossible method of capturing significant amounts of carbon. Planting trees is another popular suggestion for sequestering carbon, but a more traditional method has not been mentioned to the best of my knowledge.
Building up the soil is a simple low-tech technique for sequestering carbon. For centuries, careful farmers have realized how to build up the fertility of the soil, not really thinking in terms of carbon sequestration.
Commercial US agriculture is largely based on "robbery agriculture," as the great German chemist of the century and a half ago, Justus von Liebig, put it. When I published my book, Farming for Profit and a Hungry World, 30 years ago, I discovered that US agriculture was eroding about 30 pounds of soil for every pound of food it delivered to an US table. At the same time, my research for the book found that US agriculture was burning about 10 calories of fuel for every calorie of food that it was delivering to a US table.
I have no reason to believe that these imbalances have gotten any better since then. I strongly suspect that they have gotten worse.
So, the plan for reducing carbon by way of agriculture is to grow corn, perhaps the most industrialized crop, in order to produce ethanol. This process produces more energy than it consumes, only if a lot of credit is given to the energy value of the residues, which are fed to cattle. Even then, the net gain in energy is minimal and ignores the intensive consumption of water and the carbon released from the soil.
Yet, careful agriculture, by putting more organic matter back into the soil, builds up fertility, while sequestering carbon. This kind of traditional agriculture uses less mechanization.
Does this technology mean that society must revert to turn more people into downtrodden farmworkers? Capitalism might impose such an imperative, but the technology certainly does not. After all, many Sunday newspapers have a special section devoted to gardening because people find that sort of activity pleasant.
Final caveat: I do not pretend to have developed detailed data on how much a rational and cultural system could contribute slowing down global warming, but I do know that the direction we are heading is wrong.
10 comments:
Perelman
would like to hear more.
the other day i heard a man who claimed to be a scientist advocating tubes in the ocean that would pump nutrients to the surface to feed algae etc.
he seemd not to be too concerned about the effect this would have on ocean ecologies.
my own, completely ignorant, thought some years ago was capturing an amount of sea water from wave and tide action each day, growing algae, dredging the algae out and doing it again... i have no idea if this is feasable on a scale that would make a difference, but at least it would not be destroying one ecosystem to save another.
that said, it seems to me that a lot more can be done by way of simple conservation... using electric cars at least in the cities where they are currently technologically perfectly feasible, for example.
but the problem is that none of the deciders think the problem is urgent enough yet to actually do something.
Pumping nutrient to encourage algae bloom might work, but as you mentioned, it might also have bad ecological reactions. Since nobody to my knowledge has scaled up such an operation we do not know.
We are in deep doo doo now & have to do something. My suggestion will not be taken seriously since no corporate interests are involved.
There appears to have been some adaptation to higher energy costs. 'No till' or 'low till' farming. The corporate model means that heavy use of pesticides has replaced some of the use of the tractor.
The corporate agro-forestry models mimmicks corporate agriculture with the exception that - with absentee landholdings - they simply don't manage the land in any effective way. The weeds are left to grow and overtake the countryside.
Whilst they claim that covering the Southern Hemispher with monoculture tree plantations is 'carbon sequestration' it must be a major contributor to global warming. Most have replaced native forests, many 'old growth'. Hundreds of years of accumulated forest mulch is piled up and burnt along with the rest of the most of the clearfell biomass before the alien trees are planted. The the process repeats every 12-20 years when the trees are harvested for woodchip.
This is a test to see if I can leave a post. I've been having trouble here.
Another appropriate technology that is currently under development at the Hawaii Natural Energy Institute is the flashcarb process of creating charcoal
This can take coppiced wood or pelleted perennial grasses and create charcoal with high efficiency ... the part presently under development is the catalytic conversion of the exhaust gas to eliminate pollution.
This can provide carbon neutral biomass coal simply by burying enough of the charcoal to compensate for carbon consumed in production of the feedstock ... and sequestration of carbon by simply burying much or all of the charcoal produced. And, of course, shallow burial of the charcoal in land like an exhausted strip mine is also one step toward rehabilitating the site and regaining heavily degraded land for permaculture production.
CCS is being taken very seriously by corporate types at places like the Electric Power Research Institute. They see it as potentially being able to reduce emissions from coal-fired plants by 95% or more. Basic plan is to liquify it then bury it. In the right sort of saline pits, it will bind and be no problem.
However, the tech on this not ready yet, still some ways away. The problem the world is facing is that India and China will be massively increasing their electricity generating capacity enormously over the next 15 years or so. CCS will probably not be ready to help much with this wave of building, which will probably largely use currently available techs. That leaves us pretty much with some pretty hard choices, mostly current coal or current nuke facilities, although wind can help some (solar will not be ready), and India is developing an alternative nuke tech, thorium reactors.
in other words we will end the world so the chinese can go "vroom vroom" just like us.
I don't really have a comment on this, but I thought Perelman and any others intrigued by the idea of building up soil might be interested in this essay by physicist Freeman Dyson:
http://www.edge.org/3rd_culture/dysonf07/dysonf07_index.html
The essay is called Heretical Thoughts about Science and Society. Here are some of the key points from the intro:
>>The number that I ask you to remember is one hundredth of an inch per year. Now I will explain what this number means. Consider the half of the land area of the earth that is not desert or ice-cap or city or road or parking-lot. This is the half of the land that is covered with soil and supports vegetation of one kind or another. Every year, it absorbs and converts into biomass a certain fraction of the carbon dioxide that we emit into the atmosphere. Biomass means living creatures, plants and microbes and animals, and the organic materials that are left behind when the creatures die and decay. We don’t know how big a fraction of our emissions is absorbed by the land, since we have not measured the increase or decrease of the biomass. The number that I ask you to remember is the increase in thickness, averaged over one half of the land area of the planet, of the biomass that would result if all the carbon that we are emitting by burning fossil fuels were absorbed. The average increase in thickness is one hundredth of an inch per year.
>>The point of this calculation is the very favorable rate of exchange between carbon in the atmosphere and carbon in the soil. To stop the carbon in the atmosphere from increasing, we only need to grow the biomass in the soil by a hundredth of an inch per year. Good topsoil contains about ten percent biomass, [Schlesinger, 1977], so a hundredth of an inch of biomass growth means about a tenth of an inch of topsoil. Changes in farming practices such as no-till farming, avoiding the use of the plow, cause biomass to grow at least as fast as this. If we plant crops without plowing the soil, more of the biomass goes into roots which stay in the soil, and less returns to the atmosphere. If we use genetic engineering to put more biomass into roots, we can probably achieve much more rapid growth of topsoil. I conclude from this calculation that the problem of carbon dioxide in the atmosphere is a problem of land management, not a problem of meteorology. No computer model of atmosphere and ocean can hope to predict the way we shall manage our land.
anonymous said: " I conclude from this calculation that the problem of carbon dioxide in the atmosphere is a problem of land management.."
No and yes. No because those involved in burning old growth forest across the entire Southern Hemisphere in the last decade knew the implications for climate change. So the disaster is essentially on derived from malgovernance.
Yes, because if we could get large corporations and their servant governments to address the problem then its likely that most of the solution would revolve around land management.
From my inbox today:
"On global warming, FPIF ontributor Michael Shank recommends that the European Union consider including old-growth forests as a category of offsets in its cap-and-trade policy. Old-growth forests harbor something called arbuscular mycorrhizal fungi, which in turn produces a protein called glomalin. "According to a University of Maryland study, glomalin accounts for almost a third of all the carbon stored in soil,"
Shank writes in The Soil That Saves. "Factor this with scientific
estimates that soil has the potential to sequester 40-80 billion metric tons of carbon over the next century and the conclusion is simple: protect old-growth forests. The soil found in old-growth forests may be one of our most valuable assets in our efforts to slow climate change..."
From:
World Beat
by JOHN FEFFER | Monday, October 8, 2007
Vol. 2, No. 41
Links:
'study': http://www.ars.usda.gov/is/AR/archive/sep02/soil0902.htm
'Soil That Saves'
http://salsa.democracyinaction.org/dia/track.jsp?v=2&c=5H7pFivs7nBQLgI2YUolw6iaiqs4pluk
Just to clarify, brenda, "anonymous" (me) didn't say that thing about land use. Freeman Dyson said it, and I just passed it along. It sounded interesting, but I don't really have the background to evaluate it.
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