Garnaut stresses importance of measurement

Says Prof. Ross Garnaut in Australia, who heads an independent commission on climate change commissioned by Australia's Commonwealth, State and Territory Governments:

What grass farmers have known all along—research shows grass sequesters carbon

By Martha Holdridge, West Wind Farm

Editor's note: This article is reproduced with permission from the Summer 2008 Grassfed Gazette, published by the American Grassfed Association.

American Grassfed Association member Martha Holdridge, owner of West Wind Farm, used soil samples to determine that her West Virginia farm sequestered 15 tons of CO2 per acre over the past four years (photo by Kenny Kemp, Charleston WV Gazette).

From 1987 to 2007, at West Wind Farm, we regularly sent soil samples from our pastures to the West Virginia University (WVU) testing lab--in some years requesting organic matter tests. In those same years, there has been increasing public alarm about greenhouse gasses and global warming. In the fall of 2007, Dr. Ed Rayburn, extension forage agronomist at WVU, reminded me that an increase of organic matter in the soil means that carbon dioxide (CO2) is being drawn from the air into the soil. He kindly agreed to calculate the rate of carbon sequestration in the pastures of West Wind Farm.

Our average organic matter in 2002 was 4.1 percent, in 2004 it was 7.0 percent, and in 2007 it was 8.3 percent. According to Rayburn’s calculations based on a 2-inch deep sample, over five years (2002-2007) we had sequestered 15 tons of CO2 per acre or four tons of carbon per acre.

Measuring or estimating soil carbon

How do you measure or estimate soil carbon?

Here are some handbooks

1. Peter Donovan. Measuring soil carbon change: a flexible, practical, local method. 2010. A basic guide for do-it-yourselfers and the method for the Soil Carbon Challenge. Includes planning worksheet and plot data sheets.

2. Pearson, Timothy, Sarah Walker, and Sandra Brown. 2006. Sourcebook for Land Use, Land-Use Change and Forestry Projects. Winrock International.
http://www.winrock.org/ecosystems/files/Winrock-BioCarbon_Fund_Sourceboo... (661 K pdf file; right click and "save link as" to download)

Winrock also has a sampling cost calculator available from
http://www.winrock.org/ecosystems/tools.asp

3. Stolbovoy, V., Montanarella, L., Filippi, N., Jones, A., Gallego, J., and Grassi, G. 2007. Soil sampling protocol to certify the changes of organic carbon stock in mineral soil of the European Union. Version 2. European Commission, Joint Research Centre. ISBN 978-92-79-05379-5
http://eusoils.jrc.ec.europa.eu/esdb_archive/eusoils_docs/other/EUR21576...

summary poster:
http://eusoils.jrc.it/ESDB_Archive/eusoils_docs/Poster/Soil_Sampling.pdf

4. McKenzie, N., Ryan, P., Fogarty, P., and Wood, J. 2000. Sampling, measurement, and analytical protocols for carbon estimation in soil, litter, and coarse woody debris. Australian Greenhouse Office, Technical Report 14.
http://www.greenhouse.gov.au/ncas/reports/tr14final.html

5. Harnessing Farms and Forests in the Low Carbon Economy: How to create, measure, and verify greenhouse gas offsets edited by Zach Willey and Bill Chameides, Duke University Press, 2007.

Carbon farming in Marin County, California

An article from ODE magazine about soil carbon research and trials in Marin County, California.

". . . John Wick--who owns this ranch in the hills of Marin County north of San Francisco with Peggy Rathmann, author of the classic picture book Goodnight Gorilla--goes on to outline the climate crisis in terms all-too-familiar to anyone paying attention to the issue. But he then offers a solution that would astonish most people, especially green activists: 'Eat a local grass-fed burger.'"

Liquid, mycorrhizal carbon not often recognized

Christine Jones published an article in the Australian Farm Journal that may help to explain why the assumption is widespread among agricultural scientists that soil carbon cannot be increased quickly. The Roth C model, for example, ignores the role of mycorrhizal soluble carbon, focusing entirely on biomass input for humification:

The quiet carbon revolution in Australia

A short article from Australia on the work of Christine Jones:

"Thousands of farmers are joining a voluntary soil carbon movement adopting specialised cropping and pasture practices to improve yields and income, while measuring loads of carbon storage on their farms."

"But the Senate inquiry, looking into the impacts of climate change on agriculture, also heard the results have been largely shunned by the science fraternity because the carbon storage data does not fit into existing carbon models."

Can we unscramble the egg?

If we quit adding carbon to the atmosphere, it won't stop global warming anytime soon. That's why people are hoping that there are ways to get the extra carbon out of the atmosphere, and that we can put these billions of tons of it somewhere safe.

Breaking apart carbon dioxide, or extracting carbon dioxide from the air, takes work. Work means energy. It's the reverse of combustion. There's a triple problem here: the technology itself, the disposal, and the energy to do the work.

It's a common saying that you can't unscramble an egg. You break an egg into a bowl, break the yolk membrane with your fork, mix the yolk thoroughly with the white, and stir it around in a hot skillet. The cooking uncurls the egg proteins, breaking some chemical bonds and causing new ones to form.

Now we've got a scrambled egg. The egg proteins won't go back to their raw configuration when they cool, and even if they did it's impossible to wield the fork in such a way as to separate the yolk from the white. Roomfuls of the latest and greatest laboratory equipment, the best Google algorithms, or even all the king's horses and all the king's men would not unscramble our egg. The mixing and cooking are irreversible processes.

It's a familiar impasse. Can we change the way we see the problem?

Feed our scrambled egg to a hen, and tomorrow she'll lay us a new egg. Her metabolism—a product of evolution rather than technology—will break down the complex scrambled egg molecules into simpler ones and reconstitute them, with losses of course, into a new, raw egg.

Offsets or ecosystem services?

In the United States, the current carbon market at the Chicago Climate Exchange buys offsets or "pollution credits" as some have called them. The amount of carbon sequestration purchased is directly related to emissions of carbon into the atmosphere by industries, for example. As the trading price of carbon offsets increases, presumably emissions will go down, but then so will the purchase of offsets.

Know-that and know-how

Will reducing carbon dioxide emissions slow down global warming? Hardly, according to the Intergovernmental Panel on Climate Change. "Complete elimination of CO2 emissions is estimated to lead to a slow decrease in atmospheric CO2 of about 40 ppm over the 21st century" (IPCC Fourth Assessment FAQ, section 10.3).

Carbon dioxide is a stable gas, requiring energy to break its molecular bonds. With 100 percent reductions in 2007, we will maintain what NASA climate scientist James Hansen calls dangerous levels—not just for a few years, but for generations. The area under the Keeling curve will remain huge, and that translates into ocean heating.

What this means is that our current widespread advocacy of CO2 emissions reduction has little leverage on what most scientists regard as the cause of global warming—the highest atmospheric CO2 levels in hundreds of thousands of years. The assumption that CO2 emissions reductions will do the trick has become popular groupthink, not subject to scrutiny because it's what we all know, and may seem like the only available option. Once again, we are goading ourselves into a gallant cavalry charge into the barbed wire.

What's needed is to reverse the Keeling curve, to quickly and significantly reduce existing atmospheric concentrations of CO2. According to NASA's figures on the global carbon cycle, fossil fuel burning represents less than 3 percent of the annual flux of CO2 into the atmosphere (3.4% according Rattan Lal's figures). The rest is biology, which also responds to human management.

The politics of soil carbon

Building soil organic matter on a large scale could reverse global warming, but it also has near-term, local benefits. These include better water cycling (fewer floods and droughts, more moderate and consistent streamflow, as well as better water quality), better mineral cycling (e.g. less nitrate pollution), increasing biodiversity above and below ground, an increase in the quantity as well as quality of human food, less reliance on chemical and fossil fuel inputs to agriculture, and greater self-sufficiency and economic independence of the agricultural sector.

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