Drink organic – its a sure way to help save the climate!

By Sam Statham
I have just done some pretty interesting statistics. They are of course rubbery, but still interesting.

They are based on our farm. I have been looking carefully at our 2010 soil test reports and calculated how much carbon has been sequestered by Rosnay since we converted it to organic farming in 1998.

In 1998, our soil contained 0.25% organic carbon. This is not unusual. The farming areas of NSW are generally as low as this, acid on top and alkaline and often salty at depth on the lower slopes. The soil is called “Sunday Soil”. It rains Friday, its too wet Saturday, you can plow it Sunday, and its too dry Monday. This is due to a lack of soil carbon and humus, caused by chemical intensive agriculture. There were parts of Rosnay that, if you used a subsoil or Yeomans plow, you would pull up 60cm cubes of solid hard set dirt. How can worms live in there?

In 1998 we began converting Rosnay not only to organic farming, but to perennial crops: vines, olives and figs. By 2010, Rosnay’s top foot of soil has an average of 1.72% organic carbon. This is an increase over 12 years of 1.47% (or relative to 0.25%, its an increase of 588%), which if you multiply by the weight of soil in one hectare one foot deep, 3658t, is 53 tonnes of sequestered carbon per hectare (//soilcarboncoalition.org/calculation). Over 12 years of organic farming, that’s 4.5t/ha of sequestered carbon per hectare per year, with more to come.

If there were a price on carbon of $40/t, we would have generated $180 per hectare, and over our 30 hectares, that adds up to $5,400 a year… Oops… Forget talking dollars for “soil farmers”, as the Carbon Farming Initiative says that soil carbon sequestration credits are not “Kyoto compliant” anyway. That CFI thing is doublespeak.

So instead, let me ask you: If it helps sequester a large chunk of greenhouse gas, what would you say to Australia phasing out chemicals in agriculture, starting with viticulture, and moving towards organic farming? If you just got half the carbon buildup that we had here, say 2.25t/ha per year, times the Aussie vineyard area of 158,000 hectares (Abare), you are locking away over 700,000 tonnes of carbon per year. Would you choose organic wine?

Driving the point even more, solid research collated by the Organic Federation of Australia says that Australia only needs to sequester a quarter our amount,  or 1.1 tonnes of CO2 per hectare, to be carbon neutral!

Of couse this pales in comparison with the carbon savings of stopping the woodchip industry. The area of Aussie deforestation each year is actually 20% more than the whole vineyard area. Thats the reverse of what we are doing. 

And sure, you can only go so far before you reach a “climax” of organic soil carbon after which the soil can no longer absorb carbon.  But its still a lot of carbon to put away for the next 10-20 years when we might run out of oil, and uranium if we are lucky.  

Its a big ask to say “drink organic to save the climate”, but even if you are a sceptic and dont trust the government, or the IPCC, at least you’ll be drinking organic wine which is better for you. You would have to drink to that!

8 Replies to “Drink organic – its a sure way to help save the climate!”

  • Very interesting and useful to understand a bit more about the science behind the soil!

  • Hi John – thats really interesting. So, if the agricultural soils have dropped from say 7% organic carbon to 1%, and the area of agricultural land in Australia is 425 million ha (4.25m km2), and 1% of organic carbon is 36tonnes/ha, then over the last 150 years we have lost 425m x 6 x 36 = 92 billion tonnes of CO2 emitted by agriculture and land clearing. Last year Australia emitted 540 million tonnes of CO2 (see //www.climatechange.gov.au/climate-change/emissions.aspx). So the total losses from our soils are 170 times our annual emissions!

  • Hi Sam,
    Spot on! I am always staggered how anything can grow in some of the farming ‘soils’ of the central west. We are so used to seeing some organic matter in our soils on the coast.
    A reminder that we all need to be mindful of all our purchasing actions. Like it or not they have real consequences.
    Keep it up mate!
    Best
    Stuart

  • Good on you Sam – here’s a little excerpt from an upcoming article of mine in the Weekend Australian magazine, partly about the soil carbon problem/solution – one of the solutions being short burst intensive cattle grazing:

    Between 1839 and
    1843, the explorer Strzelecki collected 41 soil samples around south-eastern
    Australia. The top ten samples had an average of 20 per cent organic matter
    (soil carbon), the bottom ten an average of 3.72 per cent. Today, the average
    in Australia is around 1 per cent.

  • Carbon sequestration is obvious to organic farmers. Of course there is a limit, but it is several % before it reaches equilibrium. Then it has to be maintained. Just think of the carbon that could be sequestered to return to Australian precolonisation days of ?5% in the top layer. Then there is the continuing decarbonisation (?desequestration) by much of agriculture – turn a peat bog into an oil palm grove or crop black soil plains continuously without even replacing the carbon. No wonder agricultural sequestration is not in Kyoto. A few winners and lots of losers.

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