The agricultural carbon audit scheme is still ongoing – Brian Henderson

The agricultural carbon balance is imprecise
The agricultural carbon balance is imprecise

From a broader agricultural point of view, despite the fact that it is one of the common elements of all forms of life, until a few years ago there was little or no mention of it. in industry, in the press or even in scientific journals.

But, fast forward to today and you can’t escape the word – with endless discussions about how to mitigate its emissions, sequester them, audit them, and even trade the blessed things.

Register to our daily newsletter

And today the kick-off is given to a national effort to encourage the sector as a whole to tackle the problem as the first phase of the Scottish Government’s Track 1 of its new sustainable agricultural policy opens .

In truth, when the term carbon is used, rather than referring to its elemental forms – such as diamond, graphite, coal and coke – it is simply used as shorthand for a key molecule – carbon dioxide, the combination of one atom of carbon and two of oxygen.

According to the rules of the Intergovernmental Panel on Climate Change (IPCC), which focus on the greenhouse gas potential of different chemicals, CO2 is considered the standard unit of the effect of heating pot, the other gases receiving a “CO2 equivalent” value.

And while other industry sectors have been quick to see the marketing benefits of being able to claim they are carbon neutral or negative, this exercise asks farmers to audit their businesses and assess how much they release and how much they immobilize during their operations. .

For most types of industries, this could be a fairly straightforward calculation – with transportation, electricity and other sources of energy that are consumed in the production, packaging and delivery of their manufactured goods being totaled to give a carbon footprint.

Farming, on the other hand, is a bit more complicated.

Because agriculture harnesses natural processes – which tend to be messier and harder to quantify or predict with precision.

And, along with forestry, agriculture has the unique ability to actually absorb CO2 and reduce the amount that contributes to the global warming potential of the atmosphere.

Every blade of grass, every head of corn, every grain of barley has the ability to retain CO2 through the main driving force of life on Earth: photosynthesis. And that’s what agriculture is for: harvesting solar energy from the sun and turning it into food for the human population.

But, and this is a very big but, while the accepted international protocol for calculating emissions is fairly well understood and standardized, the one for assigning credits for sequestration is less well developed.

And while the convention has taken the decision to recognize the amounts of CO2 absorbed by forestry and forests as being fixed there (despite the fact that much of it is returned to the atmosphere by combustion in woodchip boilers wood and the like), which is fixed by cereals and other crops that are consumed fairly quickly do not receive the same recognition.

So despite the fact that each acre of barley actually locks up several tons of CO2, rather unfairly in my opinion, no credit is given for this due to the fact that it will soon be consumed.

The problem is further complicated by the use of fertilizers to increase productivity, the addition of livestock to pasture to turn grass that is indigestible by humans into easily digestible animal protein – and this practice is further complicated by emissions of methane by the insects that inhabit the stomachs of the ruminants that we use to do this.

So far, it has proven difficult to calculate the amount of CO2 sequestered in grasslands, as well as that added to soils through the uptake of crop residues – and although the science is growing, it has yet to be perfected. .

Currently, the different processes used in the multitude of carbon calculators (or perhaps more accurately off-the-shelf calculators) to undertake the results can yield wildly varying results for individual farms.

So while the Scottish Government’s new carbon audit scheme may mark a starting point for benchmarking industry performance – until the science is better understood, more fairly recognized and fully integrated into a single calculator standardized, it should be seen as a work in progress rather than a final result.

Maria D. Ervin