Testing nutrient cycles for sustainability calls for nuance: smaller is not always better

Published on
June 16, 2021

Many governance regulations for circular agriculture focus on closing nutrient cycles at a regional, or even local, level. The prevailing view is that a smaller nutrient cycle must be more sustainable. Research conducted by Wageningen University & Research indicates that this perspective requires some qualification. A shorter cycle is not, by definition, more sustainable.

The case study shows that a simple measure such as no longer using South American soya leads to a chain reaction of direct and indirect responses throughout the cycle. Less soya leads to fewer cattle in Europe, which causes a shortage of manure and thus lower yields. ‘Fewer animal-based and plant-based products are manufactured. As much as 33% less, according to our estimates’, says project leader Bastiaan Meerburg of Wageningen Livestock Research. ‘This, in turn, causes an increase in the use of artificial fertilisers and food being imported from outside of Europe. Not to mention the economic effects.’

In this study, not only the direct effects of a ban on non-European cattle feed were considered. The study also took into account how chain partners, the market, and the consumer respond to changes in production and availability of feed and foodstuffs. Seven responses and their effects on sustainability have been mapped. ‘A more profound understanding of all these reactions is crucial in order to make the cycle more sustainable. No matter how much we may wish it to be different, a simple measure rarely has a simple effect within our complex food system. When judging the sustainability of nutrient cycles, nuance is key’, Meerburg concludes.

Cycle test

The researchers used the Nutrient Cycle Assessment Tool or NCAT (KringloopToets). This is a discussion and analysis model that helps stakeholders discuss the consequences of policy measures. Stakeholders from the feed industry, feedstock sector, livestock sector, national and provincial governments and NGO’s and the researchers conducted in-depth discussions in five sessions.

This study will help the agricultural sector, governments, and NGOs achieve their goals through closing nutrient cycles so that the vitality of plant and animal-based production is not affected unnecessarily.

This research was commissioned and funded through public-private collaboration Kringlooptoets 2.0 (AF-18016) (information in Dutch).