Overview
- Researchers from the University of Zurich and Agroscope recruited about 1,000 volunteers who buried cotton underwear and tea bags, retrieved them after two months, photographed decomposition, and sent the samples and soil to a lab for analysis.
- The study found the fastest decomposition and highest organic matter in private gardens, lower activity in farmland and meadows, and the slowest breakdown in manicured lawns.
- Faster decomposition generally indicates higher soil biological activity driven by microbes and soil animals, which supports nutrient cycling and crop fertility.
- The authors warn that very high nutrient levels in near-natural habitats such as forests or in heavily amended gardens can signal ecological imbalance and may call for reduced fertiliser use.
- The project produced a national 'underwear map' and one of Switzerland’s largest soil-life datasets, showing the power of simple citizen-science methods to inform local soil management and public awareness.