Intensive agriculture can impair soil quality and threaten the provision of critical soil ecosystem services. Organic
cropping systems aim to ensure sustainable production by promoting soil biodiversity to enhance soil functioning
and regulate nutrient cycling through microbial processes. While taxonomic changes in microbial community
composition in response to agricultural management are well described, there is still a fundamental knowledge
gap when it comes to the impact of cropping system on soil functional diversity. Therefore, we revisited the 42-
year-old DOK field experiment and used shotgun metagenomics to assess the metabolic potential and nutrient
cycling capacities in organic and conventionally managed soils. The functional annotation of 11.4 billion reads to
universal (EC, SEED), as well as carbon (CAZy), nitrogen (NCycDB) and phosphorus (PCycDB) cycling gene
ontologies showed that manure fertilization was the main factor altering soil metabolic potential. But also,
organic management practices, such as omission of synthetic pesticides and mineral fertilization induced changes
in soil metabolic potential e.g. by enriching functional genes involved in organic phosphorus acquisition, nitrate
transformation, organic degradation and non-hydrolytic carbohydrate cleavage. Conventional systems, receiving
mineral fertilization and chemical plant protection, enriched genes associated with inorganic nutrient acquisition
and transcriptional activity. The results of this study demonstrate that cropping systems influence the functional
potential of soils, affecting fundamental mechanisms of nutrient cycling and thus soil regulating capacity.
Consequently, cropping systems can be utilized to steer the regulating potential of agricultural soils and to lower
the environmental impact of food systems.