Fertilizer: Soil, Fertility, and the Circular Future

Soil is more than dirt beneath our feet. It is a living system, a vast community of organisms, minerals, and organic matter that underpins the survival of every plant, and ultimately every human. Yet this system has been profoundly altered over the last century. Agriculture, in its drive to feed billions, has leaned heavily on synthetic fertilizers. The Haber–Bosch process, developed in the early 20th century, gave humanity the ability to capture atmospheric nitrogen and turn it into ammonia on an industrial scale. It was a revolution, making possible the “Green Revolution” of the 20th century, when global food production exploded. But like all revolutions, it came with consequences (Nature, 2020).

Synthetic fertilizers deliver crops an immediate dose of nutrients, but they do so in ways that bypass the natural cycles of soil biology. Microbes, fungi, and organic matter—the quiet engineers of fertility—lose their central role. Over decades, soils treated with nothing but NPK have become depleted, compacted, and increasingly lifeless. Scientists estimate that global soils have lost 50–60% of their organic carbon stocks since pre-industrial times, a loss that not only undermines fertility but also worsens climate change by releasing carbon dioxide into the atmosphere (FAO, 2021). 

The numbers are sobering. According to the FAO, if current trends continue, 90% of soils will be degraded by 2050. Already, Europe’s own Soil Strategy acknowledges that 60–70% of soils are unhealthy due to erosion, compaction, contamination, or over-fertilization (European Commission Soil Strategy, 2021). 

Solutions exist. Insect-based fertilizers, composts, and organo-mineral blends mimic natural processes while still delivering agronomic value. Black Soldier Fly (BSF) larvae, for example, feed on crop residues, breaking them down while enriching them with chitin and microbial metabolites. Trials show that such fertilizers improve water retention by 10–15%, equivalent to hundreds of thousands of liters per hectare. In regions like East Kalimantan or Andalusia, this is the difference between crops surviving a drought or failing. 

The circular future of fertilizer will not reject technology—it will embrace it. Precision tools can ensure that nutrients are applied where and when they are needed. Biological and circular fertilizers will close the loop between waste and soil. Meeting these targets will require systemic change, but the rewards will be immense: healthier soils, cleaner rivers, more resilient farmers, and a climate system given a fighting chance.