SOILS AND THE CIRCULAR ECONOMY
The maths show we are promoting a technology which is harming soil: in the energy-food-land trilemma yet again the land is losing out.
THE PROBLEM: AN OVERVIEW
Considering the Clean Growth Strategy, there appears to be a disconnect between government work on energy and environment. While soil is mentioned, there is much focus on how anaerobic digestion (AD) can encourage industry to produce energy from organic waste.
The water industry has been particularly excited by this and is moving fast into AD. However, while some biosources are not suitable for organic treatment, there is concern around whether those that are will all be destined for AD and not returned to soil - and the long-term aggregate consequences of this accumulated deficit.
More research is needed in this area in general but, fundamentally, waste that comes from AD has a lower carbon : nitrogen ratio. This waste is therefore being sold on as high nitrogen for fertilizer potential, but the carbon has been stripped out in the process and will not be returned to soil.
In this process we produce 100m tonnes of organic waste/year but return only 70 million tonnes to the soil. The unintended consequence of using waste for biofuels is a widening soil carbon deficit.
We are a signatory of the Food Waste Coalition coordinated by the Bio-Based Industries Association (BBIA) along with 40 cross-industry organisations, and have supported input for the initiative via the expertise of our Science Panel. The Coalition is currently working to contribute to Defra’s Resources & Waste Strategy, published December 2018, in support of mandatory separate food waste collections for households and businesses as central to a circular economy approach.
More information on the Coalition’s call in Resource Magazine, here.