Science Lagging Practice

When a highly respected scientist such as Dr YN Chan produces a report which says we can't sequester carbon except by using traditional fertiliser, Science has a problem. Farmers who are growing carbon in their soils know these results are wrong. Scientists we speak to are surprised at the results. But Science has never been able to justify any land management approach that it did not originate: eg. planned grazing or pasture cropping or zero tillage. To find for the petrochemical companies and against grass-roots-developed natural systems has caused some cynical remarks.

Dr Yin Chan is always careful to be scientifically correct whenever he discusses his results. Not so the ‘communications’ experts massaging the media. The Doctor says of his investigation, that no statistical difference was found for all options except pastures improved with phosphate fertiliser. He doesn’t discount the possibility that other options could have an effect. He says the methodology – paired paddock comparisons - and the ‘field variability’ in samples could easily have ‘masked’ any differences.
But in the Booklet which reports the results, the headline reads “Pasture types do not affect SOC” which is very different to the text beneath: “We found no significant differences in SOC stocks between introduced or native pastures, and between annual and perennial pastures.”
This study had two “findings” reports – an interim report released in July 2009 and the elaborate Booklet “A Farmer’s Guide To Increasing Soil Organic Carbon Under Pastures" in March 2010.*
One can judge by the tone of the ABC Rural report, the direction of the spin: “The latest science has debunked theories that rotational grazing methods can dramatically improve carbon storage in your soil. Dr Yin Chan of the NSW Department of Primary Industries says they compared carbon sequestration under set stock grazing compared to rotational grazing, native versus introduced pastures, and perennial versus annual plants. Dr Yin says none of those methods increased the amount of carbon taken up by soil in paddocks. He says adding phosphorous fertiliser was the only significant way to improve pasture production and soil carbon.”
He said no such thing. He was careful to say: "Actually after we got all the data and compared them statistically there's only one treatment we can find a statistical difference and that's due to P fertilisers," says Dr Yin Chan.
Dr Chan was not ‘debunking’ anything.

* Chan, YN, Oates, A., Lui, DL., Li, GD., Prangnell, R., Poile, G., and Conyers, MK. (2010). "A farmer's guide to increasing soil organic carbon under pastures", NSW Industry & Investment, Wagga Wagga, NSW