Carbon profiling and organic agriculture

Large scale agriculturalists and primary producers have recently become interested in measuring their carbon profiles. This may be accounted for in terms of sound economic management, and the type of foresight which anticipates the introduction of government policy and other compliance imperatives. Within this analytical environment, there is renewed demand for comparative studies which measure the approximate carbon profiles of organic and conventional agricultural technologies.

In a field-based trial organised through the University of Nottingham, researchers concluded that organic weed control required almost double the amount of energy per hectare of wheat production compared with conventional control methods. In terms of carbon dioxide emissions, they estimated between 49 and 59 kg per tonne of grain as a consequence of organic weed control. Compare this with the 16.5 kg per tonne estimated from the conventional approach to weed management. The question then arises, to what extent might the elevated carbon profiles of organic weed control be offset by advantageous conditions within the productive supply chain?

It is for example, advantageous to alleviate the additional energy expenditure associated with herbicide manufacture, and the other synthetic inputs required by a conventional production model. Once the energy expenditure is balanced to include fertiliser, pesticide, and similar treatments the carbon dioxide emissions rise dramatically from 16.5 kg to approximately 39 kg per tonne of grain production.

Of course, the anticipated advantages of organic production relate specifically to consumer safety and a wider spectrum of ecological practices which promote sustainability and stability of important food resources. It also needs to be clarified that specific unit energy studies are disadvantageous to smaller operations. Once organic farming units increase in scale so that yields approach those established through conventional cropping, these variations in carbon profile are likely to be revised.