The DOK trial: organic farming, fertility and biodiversity
Switzerland’s DOK experiment compares biodynamic, organic and conventional systems over decades, following production and soil functions.
Comparing whole systems
DOK derives from the German names of the three systems. Near Basel, multi-year rotations differ in fertilisation, organic-material processing and crop protection, assessing long-term effects of overall management.
The 2002 publication
Paul Mäder and colleagues reported 21 years of results in Science. Organic systems averaged 20% lower yields, 34–53% lower fertiliser and energy inputs and 97% lower pesticide use. The results connect output with resources and soil condition.
More soil life
Organic treatments showed greater soil-organism activity and diversity and better structure. Differences included microbes, earthworms and soil insects. Organic inputs and management were associated with an active community.
Carbon changes take time
FiBL’s summary reports significantly higher carbon in organic systems after 22 years. Biodynamic management using composted manure had particularly positive carbon and biological-quality development.
Continuous observation matters
DOK shows why production, inputs and biology belong together. Long records distinguish accumulated changes from annual variation.
Our field work
We plan long-term microbiology, organic-matter and tree-response records with repeated observations following our School training.