Soil test launched to help farmers monitor carbon capture
© Eurofins A new soil test which uses near infrared spectroscopy (NIRS) to measure soil organic matter and track its carbon content over time has been launched by Eurofins Agro UK.
The company says the test will allow farmers to measure the amount of carbon being sequestered in soil, as well as helping them to make decisions about how to reduce emissions, improve their farming system and meet carbon targets.
See also: What your arable weeds are telling you about soil health
It is well known that taking carbon out of the atmosphere and storing it in the soil can help in the fight against climate change, says Sophie Cath, business development manager at Eurofins Agro UK, who adds that the carbon is contained in soil organic matter.
In that form, its presence helps with soil function and structure, assisting with nutrient cycling and water retention, forming the basis of a healthy soil, she notes.
Storing more carbon in the soil will not only help to improve resilience, it also has the potential to be an additional income stream in the form of carbon credits and meet supply chain requirements for sustainable food production, she adds.
“Soil Carbon Check is a yearly soil analysis designed to provide the carbon capture data required,” she says.
“The detailed report that farmers receive gives insight into current soil carbon levels, the different carbon fractions within that total, advice on how to improve carbon storage, and a carbon calculator to test different scenarios.”
As well as measuring soil organic matter and determining how stable that carbon is, the test also measures soil inorganic carbon, before establishing a total carbon content of the soil.
It also looks at the soil’s active carbon content – the amount that is cycling nutrients and providing food for the soil microbes – so that the effect of changes in agronomic and soil management practices can be monitored.
Other soil health measurements provided include ratios of carbon, nitrogen, sulphur and clay – with the C:N ratio being a good indication of how balanced soil microbes are and if they will help with the release of nutrients, stresses the company.
Using all this information, practices and inputs that might improve carbon capture can be considered, as the company is also launching a free online soil carbon calculator. This will provide a “What if?” function to test different approaches.
It costs £55 per soil test, which includes the detailed report. The tests should be carried out annually, in similar conditions.
Analysis: NIRS – is it a better way of determining carbon content?
NIRS and similar methods provide a quicker way to carry out a range of soil analyses than conventional chemical analysis, but the data must be calibrated against a library of data obtained by conventional means, say Rothamsted researchers.
While it’s exciting and opens up possibilities because it is quicker and easier than traditional methods – allowing more samples to be handled and more measurements completed – it doesn’t provide more information than before, they note.
Organic carbon content is a key soil property which should be monitored, says David Powlson, who adds that it changes very slowly over time, making it difficult to detect trends within a short period.
Information on the carbon to nitrogen ratio in the soil is less beneficial to farmers, he believes, as most soils have a very constant ratio of about 10-12.
Short-term issues, such as the addition of a high C, low N material such as paper crumble, will upset this balance as the soil microbes will absorb nitrogen as they break it down, but a measurement isn’t required to understand this, he suggests.
“You get a similar effect with cereal straw, leading to a short-term lack of nitrogen for crops,” says Prof Powlson.
